‐ Lincoln, on the other hand, did not have Shakira.
‐ There is so much patriotism on the left, anno Obama, that they might now own more flags than Che shirts. Patriotism should not be the sport of partisanship. Obama himself, a careful student of his own life, is mindful of the opportunities he has enjoyed, and we join him and his followers in their gratitude to the country that extended them. Their enthusiasm is our challenge. To win again, we cannot simply wave the flag; we must advance better policies and principles, and make more compelling arguments. We have some of them, and will have to fashion others.
‐ Barack Obama wants Timothy Geithner to administer the Treasury. That means, among other things, overseeing the IRS. Byron York's just-the-facts report for SMALLCAPSNational Review Online summarizes why Geithner should be rejected: "What senators learned at the gathering was not only that Geithner had failed to pay self-employment taxes during his time at the International Monetary Fund. They learned that the IMF had repeatedly informed Geithner, as it had all its employees, of his obligation to pay that tax. They learned that Geithner signed documents saying he would pay the tax. And they learned that Geithner accepted IMF reimbursement for Social Security and Medicare taxes that he had not, in fact, paid. . . . In addition to his payment of the unpaid self-employment taxes, Geithner also had to pay $5,566 to cover other shortfalls in his tax payments, for a total of $48,268 in back taxes and interest." An administration with messianic pretensions is vulnerable to the venial. Obama claims to prize competence above all, but the exchequer will not be well served by the elevation of a man with Geithner's cavalier attitude toward financial obligations. On economic issues Obama has access to a deep talent pool. Republicans should encourage him to go fishing for a more credible Treasury secretary.
‐ If Eric Holder were a Republican, his nomination to be attorney general, and even more so his confirmation, would be inconceivable. As Clinton's deputy attorney general, he was a central figure in the disgraceful pardon of Marc Rich, one of the FBI's most wanted fugitives, who evaded arrest for racketeering, tax evasion, and trading with the enemy (Iran) for two decades. Currying favor with Rich's lawyer, Jack Quinn, who was well positioned to advance Holder's hope to become attorney general in a Gore administration, Holder tried to pressure prosecutors into negotiating with the fugitive's representatives. When that proved unsuccessful, Holder ran roughshod over his department's protocols and shielded Clinton from prosecutors' strenuous objections to a pardon, which Holder recommended. Moreover, Holder pushed through Clinton's 1999 commutations for several terrorists whose Puerto Rican separatist organizations had carried out over 130 bombings in the United States. Riding the wave of good will toward Obama, Holder will likely be confirmed. He is a terrible choice.
‐ The Obama campaign's anti-war critique of Bush security policy was doctrinaire. The Obama administration — due as much to good fortune as to pragmatism — is signaling more flexibility. Bush's successful troop surge in Iraq paved the way for the gradual reduction of forces that Obama has approved, rather than the hasty pullout he once called for — and he is wisely keeping on Robert Gates, Bush's defense secretary. On Guantanamo Bay, he now acknowledges that the once-promised immediate closure is not possible because the once-promised trials for detainees would be impractical. There are, Obama has discovered, people who mean the United States great harm but cannot be convicted under our rigorous civilian-court standards, so Gitmo must remain open until Congress enacts new rules for detaining enemy combatants. On surveillance, Senator Obama eventually voted for the reforms he derided during the primary campaign; as president, he now stands to benefit from the debunking of the Democrats' "domestic spying" smear against Bush — a specialized federal court having reaffirmed the president's power to authorize national-security surveillance without court warrants. Perhaps Democrats will take security more seriously now that they're accountable for it.
‐ Left-wingers such as House Judiciary Committee chairman John Conyers demand a special commission to investigate Bush's "crimes." Obama, however, now grasps that such circuses would dent his carefully crafted "unifier" image and have a chilling effect on intelligence officers. So he vaporously talks down investigations while leaving the prosecution door slightly ajar for "blatant" crimes, lest his base revolt. Speaker Pelosi echoes this script. Let's hope the Democrats prove capable of distinguishing between crimes and disagreements with their party's platform.
‐ The next secretary of state, Hillary Clinton, told her fellow senators that she was all for "smart power." Right, then — we thought there was something wrong when Colin Powell and Condoleezza Rice embraced "stupid power." If smart power means the patient deal, the well-distributed subvention, the compelling message, and the clever feint, then every successful empire uses it. But smart power, in common parlance, is often the nostrum of those leery of exercising plain old power, or force. If that notion gets abroad, not all the smarts in the world will make friends secure or enemies anxious. If Mrs. Clinton believes such talk, she may be one of the weaker members of Obama's team of rivals.
‐ The media did not pay much attention to Joe Biden during the 2008 presidential campaign, in part because they were too busy with Sarah Palin: Did she censor books in her local public library? (No.) But Biden has a rich history, including of braggadocio. He has boasted of his IQ, academic standing, and other things (not accurately). And he recently said, "I'm the most experienced vice president since anybody." Oh, really? Take just two recent vice presidents: Cheney and Bush. Cheney had been a presidential chief of staff, a House member, a House leader, a defense secretary, and a CEO. Bush had been a House member, a party chairman, envoy to the U.N., envoy to China, and CIA director. The point is not to run a contest — but rather to say, What is it in Joe Biden that makes him say self-aggrandizing and false things? Bill Clinton once said he was the first president ever to know anything about agriculture. (Several presidents had actually been farmers.) This is a disease for which there is apparently no cure.
‐ Some employees are simply irreplaceable. Take Michelle Obama, for example. The University of Chicago Medical Center hired her in 2002 to run "programs for community relations, neighborhood outreach, volunteer recruitment, staff diversity, and minority contracting." In 2005 the hospital raised her salary from $120,000 to $317,000 — nearly twice what her husband made as a U.S. senator. Oh, did we mention that he had just become a U.S. senator? He sure had. Requested a $1 million earmark for the UC Medical Center, in fact. Way to network, Michelle! But now that Mrs. Obama has resigned, the hospital says her position will remain unfilled. How can that be, if the work she did was vital enough to be worth $317,000? We can think of only one explanation: Roland Burris's wife wasn't interested.
‐ NR argued that, while the Senate may have had the right to reject the appointment of Roland Burris to Barack Obama's vacated seat, it would be unwise to do so, the corruption of the process inhering in the appointer, Governor Blagojevich, not the appointee. There was never any question that the Senate would take our advice — not for our reasons, but out of sheer racial panic. Once a black man was put forward for a seat that another black man had held, even senatorial pride could not stand against him. And even though the former black senator left his seat because the nation gave him another one in the Oval Office, the tableau of black victimhood is still our pietà. Post-racial America: still late for its debut.
#page# ‐ Democratic Washington is consumed by the alleged need to pass a "stimulus bill" that would keep consumption strong in the short run. When the federal government has attempted such fine-tuning of the economy before, it has most often failed. Congress seems likely to throw money at infrastructure without much regard for bang-for-the-buck, since its object is simply to get money out the door (or, more crassly, to reward key Democratic constituencies). Even if you buy President Obama's numbers, the result would be $275,000 of federal spending for each job saved or created. Meanwhile Obama has given no indication that he will lift a finger to stop tax rates from bouncing up in 2011. We are stumbling toward a milder version of the policy mix of the late 1960s and 1970s: loose money and high taxes. So it is encouraging, if only slightly, to see the Republican Study Committee, a group of conservatives in the House, get behind a package that might actually promote long-term growth. They want to cut taxes on investment — including not only the type of investment that yields capital gains for business, as important as that is, but the investment that middle-class parents make in their children. The RSC is not getting much attention right now, but this is how constructive policy change happens: after the alternatives are tried.
‐ The current financial disorder results in no small part from political monkeying with the credit markets. Obama offers as an antidote more political monkeying with the credit markets. He intends to twist the arms of bankers who have accepted bailout funds, insisting that they lend more aggressively than they might otherwise be inclined to do. "We don't want them to sit on any money that they get from taxpayers," says Obama's right hand, David Axelrod. Some people never learn: Overaggressive real-estate lending and excessive risk-taking were the original problems, no? With the government leaning on a damaged banking sector to take on yet more risk, the bailout game has become a trillion-dollar pie-eating contest in which the prize is another pie.
What's a poor ideologue like me to make of that?
Now before I go on, I need to clarify something about what I mean when I say I'm an ideologue. It's true, there's a venerable tradition in conservatism that doesn't like ideology. H. Stuart Hughes's famous aphorism "Conservatism is the negation of ideology" earned applause from no less than Russell Kirk. But Kirk was talking about such poisons of the mind as Jacobinism, Bolshevism, fascism. What Barack Obama seems to have in mind is nothing more than disagreement.
Now whatever your positions on trade or immigration, it's hard to see why they should be chalked up to bitterness and bigotry simply because they differ from President Obama's.
As a matter of political strategy, Obama is trying to preempt any criticism by casting it as intellectually illegitimate. For instance, at a much-discussed press conference on the economy, then-President-elect Obama cast himself as an open-minded pragmatist. He said that he's receptive to new ideas no matter the source, Republican, Democrat, conservative, liberal. But he also insisted that the one thing we all know is: "Only government" can fix the mess we're in.
Some of this is conventional politics, particularly Democratic politics. All presidents like to claim they represent the reasonable center, and cast their opponents as sectarian, or worse. Franklin Roosevelt was a champion of this sort of thing, describing his critics as puppets of the plutocracy. Harry Truman accused Thomas Dewey of being a patsy for a Hitlerite cabal. LBJ said that Goldwater was an apostle of "hate." Richard Nixon claimed to speak for the silent majority, not the damned hippies. Bill Clinton linked his critics to the Oklahoma City bombers. In many respects, Obama's rhetoric is more respectful and inclusive than that of his predecessors.
But one senses in Obama that he also believes this stuff at, dare I say it, an ideological level. And that's the point. The "end of ideology" has always been an ideological siren song for planners, an intellectual utopia for liberals desperate to cut short inconvenient debates. Its tune is a prelude to the chorus that pines for a "New Politics" and even "New Men." It assumes that people like Obama know all they need to know about how to run a country and now it's just a matter of logistics and organization; that, as John F. Kennedy put it, "most of the problems . . . that we now face, are technical problems, are administrative problems." Or, as Michael Dukakis put it in 1988, the issue is competence, not ideology.
The quest for a post-ideological world is not only fool's gold; it bespeaks a mindset that is ultimately inimical to the spirit of democracy. The desire for an end to ideology is really the desire for total victory over your opponents. There will always be ideological disagreement because people's values, aims, and principles will always differ. And if saying so marks me an ideologue, so be it.
‐ A number of erstwhile supporters of the $700 billion Troubled Asset Relief Program have expressed their dissatisfaction with the way the initial $350 billion has been spent. Count us among them. The bailout was hard to swallow in the weeks following the collapse of Lehman Brothers and the subsequent cessation of nearly all commercial lending, but we found persuasive the argument of Treasury Secretary Henry Paulson and Fed chairman Ben Bernanke that an immediate and massive government intervention was needed to stave off a total financial collapse. The passage of the TARP signaled that the U.S. government stood behind the banks, and the acute crisis of confidence appears to have passed. The problem is that somewhere along the way, the TARP became a kind of blank-check authority for the Bush administration, which misused it to bail out the auto companies. This comes close to an unconstitutional delegation of legislative authority to the executive branch, and now that Congress has released the second $350 billion, that concentrated power lies in Obama's hands.
‐ Robert Rubin, dean of the Goldman Sachs Democrats, is resigning from the board of Citigroup. Rubin served President Clinton as Treasury secretary and is at the center of a group of influential Democrats who dominated economic policy during the 1990s and who are set to do the same under Obama. Let us hope they provide better returns to the government than Rubin managed at Citigroup, which pocketed a $300 billion government handout after suffering gargantuan losses on ill-advised subprime-mortgage investments. Still bleeding, Citigroup was forced to sell its brokerage business, Smith Barney, to raise cash. For his achievements, Rubin was paid some $115 million — something to keep in mind when the Obama administration, stocked with Rubin acolytes (Geithner, Summers, Orszag) starts prattling about excessive executive pay.
‐ On May 9, 2001, President Bush unveiled his first set of nominees to the federal appellate bench. Among them were Barrington Parker and Roger Gregory, both former Clinton appointees. These nominations were a rare gesture of bipartisanship in judicial politics, but instead of reciprocating, Democrats prevented the Senate from even taking an up-or-down vote on many of Bush's judges. Eight years later, President Obama talks a good game about post-partisanship and "transcending" traditional politics. If he wants his deeds to live up to his words, he should renominate Peter Keisler, a co-founder of the Federalist Society, to the U.S. Court of Appeals for the D.C. Circuit. Other good choices can be found for the U.S. Court of Appeals for the Fourth Circuit, where all of Bush's nominees — Robert Conrad, Rod Rosenstein, Steve Matthews, Glen Conrad — have won praise from both sides of the aisle. As a senator, Obama exhibited a conspicuous lack of bipartisan initiative, voting against confirmation of both John Roberts and Samuel Alito, and even voting to filibuster the latter. Including a few Bush picks among his early nominees would demonstrate Obama's good faith and correct an injustice that has diminished the presidency and our constitutional order.
‐ Barack Obama went to a dinner with conservative columnists at George Will's house. By all accounts charming and well-informed, Obama wanted to make a gesture toward the civil discourse he talks about so often. Good for him.
‐ Democrat Charlie Rangel wants to bring back the draft. His chances of success are only slightly better than they were in 2004, when the House defeated his bill by a vote of 404–2. He is raising the issue in order to disseminate once again the canard that the poor are bearing a disproportionate share of the nation's war-fighting burden. In fact, a 2005 Heritage Foundation study found that the opposite is the case. In 1999, 18 percent of military enlistees came from the poorest quintile of the population. In 2003, that number dropped to 15 percent. By contrast, the percentage of enlistees from the richest quintile rose from 19 percent to 22 percent over the same period. Nor do minorities wind up as cannon fodder on the front lines. Blacks and Hispanics make up 27 percent of the population, but 20 percent of the military dead in Iraq to date. We would send Rangel the statistics, but we're not sure which apartment to mail them to.
‐ A law passed in a panic over tainted toys from China now threatens to put thousands of small American vendors out of business. The Consumer Product Safety Improvement Act requires all toys and clothes sold to children in the U.S. to be tested by third parties for lead and other chemicals. This isn't a big problem for large chains like Mattel, but for people like Michael Secore and Cecilia Leibovitz, who make toys and sell them from their home in Vermont, the new regulations are prohibitively expensive. The act is a case study in unintended consequences: Congress aimed for Beijing and hit Montpelier.
‐ Should a municipal utility district in Austin have to ask the U.S. attorney general before it moves a polling place across the street? The Voting Rights Act has been interpreted to answer yes. Because Texas was found to engage in discriminatory practices in 1975 — by not supplying election materials in Spanish — the whole state is a "covered jurisdiction" that has to get "pre-clearance" from Washington before it changes even the most trivial of its election practices. When Congress reauthorized the Voting Rights Act in 2006, it declared that the rules would stay in effect for another 25 years. Getting out from under the rules is theoretically possible, but the procedure is onerous. The Supreme Court has agreed to consider a constitutional challenge to the law brought by that utility district. Constitutional or not, the law is certainly senseless. Most liberals these days believe that felons should regain the right to vote after serving their time. The covered states have served enough time to regain the right to set their own election procedures.
‐ The weather doesn't always cooperate with the plans of human beings, but thankfully, it has agreed to work with the U.S. political timetable. Within a week of Barack Obama's inauguration, climatologist Jim Hansen announced that the U.S. had "only four years left" to save the world from global warming. After that, it would be too late. In his scientific opinion.
‐ Events in Gaza have been explaining to the locals that messing with Israel is costly. The lesson is painful, and may well become more painful if it is not properly learned. The surprise is that Israel waited so long to take action against the Islamist extremists of Hamas who proclaim their intention to destroy it. As soon as Hamas took power in Gaza, this test of strength was sure to happen. But this is much more than an issue of Israel versus Palestinians. Willy-nilly, Israel has been caught up in the far larger and more significant dispute between secular Muslims and Islamist extremists, a dispute that has been the cause of much bloodshed ever since the Iranian revolution of 1979. Sponsoring Hezbollah in Lebanon, and Hamas in Gaza, the Iranians have established two Islamist bastions on the Mediterranean. This onward march of Iran prompts Arab regimes to recognize that they have interests in common with Israel. For all their Islamist credentials, the Saudis have at times criticized Hamas openly. The editor of al-Gumhouriyya, the Egyptian government daily, has written a series of articles with a title that President Bush himself might have devised: "Hamas, Damascus, Iran — the New Axis of Evil." Israelis, at least, are well aware that it is that axis they are now fighting.
#page# ‐ For decades now, Jimmy Carter has been a purveyor of PLO propaganda. Indeed, he has been a writer of that propaganda: He ghosted speeches for Arafat (as confirmed by the historian Douglas Brinkley, in an admiring book about Carter). But now Carter has become a purveyor of Hamas propaganda, which is arguably a step farther. In an op-ed for the Washington Post, he said that "Israel launched an attack in Gaza to destroy a defensive tunnel being dug by Hamas inside the wall that encloses Gaza." A defensive tunnel. Some in Israel pronounced themselves shocked. We might well imagine that some in Hamas were shocked, too: that a former American president — and winner of the Nobel Peace Prize — should adopt and spread their flimsiest and most brazen lies.
‐ People in Arab countries and even Iran have participated only on a very limited scale in demonstrations against Israeli action in Gaza. Palestinians in Jordan and Israel, and on the West Bank, seem to recognize that Hamas is ruining their national cause, and they stay at home. Not so in Europe. Inciting and exaggerating, the media are urging Hamas supporters to be plain Jew-haters. The BBC and the liberal papers smear Israel steadily. Some sort of prize must go to the French state-owned TV network France-2, which put out a film of dead Palestinians, supposedly recent victims of an Israeli air raid. In fact these people had been killed four years ago when Hamas itself accidentally exploded a truck in Gaza. Synagogues have been fire-bombed in Brussels, London, Toulouse, and Helsingborg in Sweden. Jews have been assaulted in Denmark, Britain, and France. The British police are warning Jews to review security procedures, and apparently Islamist extremists have a hit list of prominent Jews to attack. In Amsterdam, there has been a crowd chanting "Hamas, Hamas! Jews to the gas!" Apparently incapable of fulfillment, the Palestinian cause instead has brought the past back with a vengeance.
‐ Hitler and Churchill were both competent painters, though both showed a marked aversion to the human form, preferring still lifes and landscapes. Here comes a new national leader eager to fill a canvas: Vladimir Putin, prime minister (and president "behind the curtain") of Russia. At a charity auction in St. Petersburg, a painting by Putin fetched over $1 million. Putin's subject was a starry, snowy night sky, seen through the window of a traditional peasant's hut. "With remarkable economy," observed a British art critic, "he contrasts the warmth, light, and gaiety of the interior with the cold and darkness beyond." Just two days after the celebrity-art auction, human-rights journalist Stanislav Markelov was shot dead in a Moscow street by persons unknown, after having made a mighty nuisance of himself to the Russian authorities. A female journalist with Mr. Markelov was also killed — the 15th journalist to be murdered by unknown strangers since Putin took power. The prime minister's artistic inspirations notwithstanding, the Markelov killing fortifies the suspicion that, in Mr. Putin's case, the place of cold and darkness may be located within.
‐ Russia exports huge quantities of natural gas through pipelines in Ukraine and then onward to many countries in Europe. In the depth of a cold winter, the Kremlin decided to cut supplies. This brutal step has led to deaths, factory closures, loss of productivity, and a general dismay about Russian intentions. Ostensibly, technicalities about pricing and transit fees were the cause of the spat. On top of that, the Ukrainian currency has more or less collapsed and the International Monetary Fund is in the process of doing the customary bailout. At the end of a miserable fortnight, the two countries signed an agreement to restore gas to the shivering customers. In reality, the Russia of Vladimir Putin was demonstrating that it holds the whip hand over Ukraine, and could even bring it to its knees. The huge Ukrainian network of pipes earns $3 billion annually, and Russia, in its refreshed dreams of empire, aims to get control of this.
#page# ‐ The Chinese government has announced that March 28 will henceforth be celebrated as Serf Liberation Day in Tibet, commemorating the day in 1959 when China took full control of Tibet, sweeping away the evils of the old clerico-feudal order and bringing all the blessings of Communism and Mao Tse-tung Thought to the long-suffering Tibetan peasantry. Not all those old evils were invented by Chinese propagandists. But it has been the common opinion of mankind down the ages that native rulers, whatever abuses they might inflict, are to be preferred to foreign occupiers, whatever benefits they might bring (and the Chinese have brought precious few). The Greek poet in Byron's Don Juan, living under Turkish rule around 1790, looks back wistfully to a predecessor in the golden age of 500 B.C.: "He served — but served Polycrates – / A tyrant; but our masters then / Were still, at least, our countrymen . . ." Tibetans have lived for half a century under masters who are not their countrymen. They are second-class citizens in a nation once their own, their culture marked for extinction. Serf Liberation Day will not assuage the injustice of that.
‐ The Associated Press tells us: "A court in central China has sentenced a woman to death for hiring someone to strangle her 9-year-old son so she could have another child with her new husband without violating population laws. . . . Li initially received a death sentence suspended for two years because she had suffered from depression after having two abortions due to the rules against her bearing another child. . . . Such sentences are often commuted to life in prison. But the higher court found that her depression was not directly related to her crime." There is no excuse for this woman's murder of her child. But she lives in a sensationally brutal society.
‐ In France, Pres. Nicolas Sarkozy proposed some school reforms. This did not go down well with teachers, some of whom let their feelings be known when Sarkozy arrived in Saint-Lô for a speech. As the Associated Press put it, they "hurled shoes and other objects at police," who then had to respond with tear gas. The teachers hurled shoes? Oh, yes. Where in the world did they get that idea? And is that not exactly the kind of teacher you would want to educate your child: one who threw shoes at police?
‐ Recent reports indicate that 40 al-Qaeda members have died of the plague. On one level, it's great news when Mother Nature does our job for us. On another, it is a sobering reminder — like the fact that Gitmo detainees' health tends to improve — of the sheer primitiveness of our enemies' lives.
‐ G. K. Chesterton thought Rudyard Kipling, for all his bellicosity, best understood the arts of peace: the work of the administrator and the engineer that keeps the world going, and that is often heroic because life and death depend on its successful execution. Kipling himself could not have made this point more clearly than did the events of a recent day in the life of Chesley Sullenberger III, US Airways pilot. At the start of a routine flight from New York City to Charlotte, N.C., an act of nature intervened: Canada geese collided with the engines. Air-traffic control told Sullenberger to head for Teterboro airport in northern New Jersey. Calculating that he would not make it, he decided to land in the Hudson River instead. He brought his tons of aircraft down as smoothly as may be, and, when the plane began to fill with water, walked up and down the aisle to make sure that every passenger had gotten off safely (they had). Well done, sir. Well done indeed.
#page# ‐ Andrew Roberts, the British historian, was rung up by an "American lady" who wanted him to appear on her radio program. (The term "American lady" is his.) She was setting up a debate: Was George W. Bush the worst president in American history, or only the worst president in modern American history? Which side was Mr. Roberts inclined to take? The historian responded that he regarded Bush as a good president — which seemed to "dumbfound" the lady, and "wreck my chances of appearing on her show." We should say. A nice illustration of the media and George W. Bush, at the end of his two terms.
‐ PETA (People for the Ethical Treatment of Animals) has opened a campaign against fishing — or, in animal-rights Newspeak, against "the hunting of sea kittens." By rebranding our piscine pals "sea kittens," you see, the PETA people hope to make the killing and eating of them unacceptable. As their website asks: "Who could possibly want to put a hook through a sea kitten?" Why, anyone who enjoys a well-prepared sole meunière, surely. And where will this lunacy stop? Consider, for example, Canada geese, whose waste products are rapidly making America's parks uninhabitable, and one flock of which brought down that plane. Should we refer to these loathsome fowl as "sky bunnies"?
‐ Jim Boulet Jr. was a hero of the culture wars: As executive director of English First for more than two decades, he defended our common language against the relentless assaults of multiculturalism. He battled bilingual education, foreign-language ballots, and Puerto Rican statehood — always with a good cheer that his allies did their best to share. He was a prayerful and generous man, known among his friends for gift-giving and other acts of kindness. On January 16, at the age of 50, cancer took him. R.I.P.
‐ It's always something stupid that people remember you for. Ricardo Montalban appeared in hundreds of movies and television shows in a career that began before Pearl Harbor, yet to members of the age cohort that is now running America, he is best remembered for extolling the Chrysler Cordoba's "soft Corinthian leather." Here at National Review, Montalban made a deeper impression — as a longtime subscriber, a thoughtful conservative, and a friend of the magazine. Our publisher, Jack Fowler, recalls a National Review Institute dinner "where, nobly perturbed, he stood up and hushed the chattering crowd because Bill Bennett was speaking. Just the hint of the wrath of Khan was enough to bring instant silence." Cheesy commercials aside, Ricardo Montalban will be remembered as a perfect gentleman, courtly and patient with fans and strangers alike; as a devout Catholic; and as one of a tiny handful of performers who, when the situation required it, could actually out-overact William Shatner. Dead at 88. R.I.P.
President Obama's task in his inaugural address was to unify the country behind his leadership, so he did not give a partisan speech. He made several nods to post-partisanship, as when he pledged to get past "stale political arguments" and "worn-out dogmas" — pledges that both of his predecessors also made.
But Obama does not consider the dogmas of liberalism worn out, as his speech made clear. From the financial crisis he draws the lesson that "the market can spin out of control" when it is not kept under the "watchful eye" of government. One need not deny that government has a vital regulatory role to recognize ideology masquerading as thought.
The new president is also a man enthralled by his own novelty: We are to start taking care of our poor, and the poor of the world, and respecting our constitutional ideals. He matches contemporary liberalism's self-regard with his own.
His congressional majorities are strong, but his ambition will tax them. He is placing a large and expensive bet on a stimulus plan that seems highly unlikely to work as advertised: Even Washington may not be capable of spending money quite as quickly as Obama wants. Then, having put the economy back on track toward growth, he intends to tackle climate change by limiting carbon emissions and to further federalize health care. At some point he says he will also tackle the insolvency of our entitlement programs. These vast tasks conflict with one another, and not only in terms of time management; and Obama's history of leading a large organization begins and ends with his presidential campaign.
Nor does this list exhaust Obama's goals. He also wants to defeat our enemies and keep us safe, to retain the applause of the world, to raise taxes, to win reelection, to appoint liberal judges, and to strengthen our alliances. Conservatives should hope that he succeeds in some respects and fails in others.
Richard John Neuhaus, who died on January 8, was the most influential Catholic and Christian theologian and writer in America during the second half of the 20th century. His influence can be compared to that of Archbishop Fulton Sheen, with one important distinction: Fulton Sheen exercised his sway over the public directly, through his radio and television sermons. Father Neuhaus did so less directly, through his books and articles, through his editorship of a very important magazine devoted to religion and politics, through his friendship with Pope John Paul II, and through his impact on other theologians both in the Catholic church and in other Christian congregations. Partly for those reasons, however, Neuhaus's influence is likely to be the deeper, longer-lasting, and more extensive one.
Neuhaus began his adult life as a Canadian, a left-winger, and a Lutheran. He never lost his love for his country of birth — he spent six weeks of every year vacationing, reading, and reflecting in the Quebec countryside — his respect for a liberalism shaped by charity, or his admiration for the Lutheran tradition. He became nonetheless an American, a conservative, and a Catholic. And from these three conversions he forged for himself a distinctive religious identity that was conservative and generous, traditional and open, charitable and — yes — combative.
Neuhaus was a superb, natural controversialist. In the magazine he founded and edited, First Things, he commented on the overlapping topics of religion, culture, and politics in long, thoughtful articles and short, brilliant squibs. His wit was a vehicle for important truths, and some of his epigrams have entered the language.
Neuhaus never shrank from what he considered a necessary fight — even one with friends — when the issue was important enough. He abandoned his original allies on the left over Roe v. Wade. He later devoted a special issue of First Things to an attack on judicial supremacy that questioned whether an American political regime that tolerated mass abortions was a legitimate one. That formulation divided the Right and led to the Left's invention of the term "theocons" to demonize him and the Christian conservatives. To the end of his life Neuhaus continued to fight passionately for the thousands of innocents we kill annually.
But fighting and controversy, though necessary to the propagation of religious truth in our age, were secondary themes in Neuhaus's life. His achievements were essentially creative. He was a natural organizer who did not stop at reshaping his own religious identity. Along with Michael Novak, George Weigel, and others, he established First Things and made it the focus for an intellectually respectable resistance to the theological liberalism of the 1960s in Judaism and all Christian denominations. That achieved, he worked successfully to bring together Catholics and evangelicals — traditionally not the friendliest of fellow-Christians — in a new, unified political constituency for the life issues and other concerns of traditional believers. He reshaped that old-time religion.
Without Richard John Neuhaus, Christian conservatives would have been politically much weaker and intellectually far less formidable.
Much more could be written about his influence on Christianity in America and worldwide. But we at National Review also knew Richard as a valued colleague — our religion editor for many years — and a dear friend. Most of us have enjoyed dinners with him that would begin with a strong Beefeater martini and end with equally strong draughts of laughter. Some of us sought his pastoral advice and benefited from his wisdom. That he was just a few streets away in New York was itself a source of consolation.
We feel sorrow at his passing, but mainly for ourselves. He has gone to the Savior he served so well and faithfully. R.I.P.


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text:
\section{}

\section{Introduction}

Interfacial instabilities are of great importance in various plasma
phenomena in the universe and laboratory experiments
\cite{abarzhi10,nishihara10}.
The Richtmyer-Meshkov instability (RMI) \cite{richtmyer60,meshkov69}
is one of such instabilities that occurs when a planar shock hits
a corrugated surface of the contact discontinuity.
The RMI has been studied vigorously by the linear theory
\cite{meyer72,mikaelian93,yang94,wouchuk96,wouchuk97,vandenboomgaerde98},
nonlinear analysis \cite{zhang97,sadot98,matsuoka03,latini07,dimonte10}, and
laboratory experiments
\cite{jacobs96,brouillette99,chapman06,dimonte93,farley99,glendinning03,aglitskiy06}.

Turbulent mixing excited by the RMI often plays a crucial role
associated with plasma explosions in astrophysical objects
\cite{makee77} and the implosion in inertial confinement fusion
\cite{atzeni04,betti16}.
Interaction of supernova shocks and inhomogeneous interstellar matters
is one of the promising sites of the RMI, which could contribute to
the origin of the interstellar turbulence \cite{inoue09} as well as
the amplification of magnetic fields \cite{sano12}.
The RMI is recognized as one of the severe obstacles to prevent the
ideal implosion in laser fusion plasmas \cite{atzeni04,betti16}.
Drastic symmetry reduction results in inadequate energy gain at the end of
the process.
Therefore, the mitigation mechanisms of the RMI are paid attention
intensely in this field.

There are several effects proposed to stabilize the RMI.
The vorticity deposited at the interface just after the incident shock
refraction is the driving source of the RMI growth, while the
vorticity left in the bulk of the fluids
has been proved to be a physical agent that decreases the
growth of the contact surface ripple
\cite{coboscampos16,coboscampos17}.
However, the effect of the bulk vorticity becomes significant only
when the shock is sufficiently strong, or the compression is high
enough.
{\color{black}{%
For the RMI in plasmas,}}
a strong magnetic field can suppress the growth of the RMI when the
Alfv{\'e}n (Mach) number, which is the ratio of the linear growth velocity to
the Alfv{\'e}n speed, is less than unity
\cite{samtaney03,wheatley05,sano13}.
However, if the direction of the magnetic field is parallel to the
interface but perpendicular to the wavevector of the surface
modulation, the Lorentz force hardly works on the RMI.
Then, the suppression by the magnetic field in three-dimensional
geometry would be difficult so as in the case of the Rayleigh-Taylor
instability \cite{chandrasekhar61,stone07}.

In this paper, we focus on the effect of a density transition layer at
the interface for the suppression of the RMI.
It is well known that the smooth density structure of the interface
affects the unstable growth of surface fluctuations.
For example, the density stratification at the shear layer of the
velocity stabilizes the Kelvin-Helmholtz instability
\cite{chandrasekhar61}.
The stability condition is given by the Richardson number, which is a
function of the density gradient.
The Rayleigh-Taylor instability is also affected by the density stratification \cite{munro88,atzeni04}.
The growth rate of the instability decreases dramatically if the scale
length of the density structure is longer than the wavelength of the
Rayleigh-Taylor mode.
As for the RMI, the transition-layer effects have not been much
investigated because of the difficulty of the analytical approach
\cite{mikaelian85}.

The density transition layer is naturally formed in astrophysical
objects and laser plasmas.
The molecular clouds in the interstellar medium are modeled by an isothermal self-gravitating sphere, which is the so-called Bonnor-Ebert sphere, where a flat high-density core surrounded by a power-law envelope.
The smooth distribution of the density should affect the stability at the shock interaction \cite{klein94,nakamura06,falle17}.
In laboratory plasmas, the density distribution in the laser ablation
layer is verified to mitigate the turbulent-mixing caused by the
ablative Rayleigh-Taylor instability \cite{takabe85,betti98}.
The exponential density distribution is usually assumed at the
material interface in this case.
Thus, the RMI with a smooth layer of the density transition would have
numerous critical applications.

The goal of this paper is to obtain the suppression condition of RMI
due to the existence of the density transition layer by using
nonlinear hydrodynamic simulations.
The analytical treatment of the RMI is not straightforward when the
interface has a non-uniform density profile.
In that case, numerical simulations are a powerful tool as the first
step to examine such complicated situations and to extract the essence
of the physical basis empirically.

The outline of this paper is as follows.
In Sec.~\ref{sec2}, the basic equations, initial conditions, and numerical methods are described.
Various simulation results are shown in Sec.~\ref{sec3} to reveal the influence of the transition layer on the growth of the RMI.
In Sec.~\ref{sec4}, the physical interpretation of our findings is discussed.
Then, the suppression condition of the RMI in terms of the thickness of the transition layer is derived.
We also remark on an application of our results to laboratory laser plasmas.
Finally, the conclusions are summarized in Sec.~\ref{sec5}.

\section{Numerical Method \label{sec2}}

To study the nonlinear evolutions of the RMI, the following system
equations for inviscid fluids are solved;
\begin{eqnarray}
\frac{\partial \rho}{\partial t} + {\mbox{\boldmath{$\nabla$}}} \cdot
\left( \rho {\mbox{\boldmath{$v$}}} \right) = 0 \;,
\label{eq:con}
\\
\frac{\partial (\rho {\mbox{\boldmath{$v$}}})}{\partial t} +
{\mbox{\boldmath{$\nabla$}}} \cdot
\left[ P {\mbox{\boldmath{$I$}}}
+ \rho {\mbox{\boldmath{$v$}}}
{\mbox{\boldmath{$v$}}} \right] = 0 \;,
\\
\frac{\partial e}{\partial t} + {\mbox{\boldmath{$\nabla$}}} \cdot
\left[ \left( e + P \right)
{\mbox{\boldmath{$v$}}}
\right] = 0 \;,
\label{eq:ene}
\end{eqnarray}
where $\rho$ and {\mbox{\boldmath{$v$}}} are the mass density and
velocity, respectively, and $e$ is the total energy
    density per unit volume, $e = P/(\gamma -1) + \rho v^2/2$.
{\color{black}
The equation of state for the ideal gas is used with the isentropic
exponent $\gamma$.}

\begin{figure}
\includegraphics[scale=0.85,clip]{fig1.eps}%
\caption{
(a)
Initial setup of the single-mode analysis for the RMI.
A planar shock hits a corrugated interface between the fluid
``a'' and ``b'', where the wavelength of the surface modulation is
assumed to be $\lambda$.
{\color{black}
The characteristic quantities of this system are the incident shock
velocity $U_i$, the density jump at the interface $\rho_{a0} / \rho_{b0}$,
and the corrugation amplitude $\psi_0$.}
In this analysis, the density transition layer with a thickness of $L$
is considered.
(b)
Density distributions of the transition layer adopted in this
analysis, which are the $\tanh$-type (black), linear-type (red), and
$\exp$-type (green).
The transition layer is located at $-L/2 \le x \le L/2$ initially.
\label{fig1}}
\end{figure}

We adopt a single-mode setup for our numerical analysis, which is
illustrated by Fig.~\ref{fig1}(a).
Two fluids with different densities, $\rho_{a0}$ and $\rho_{b0}$,
are separated by a corrugated interface located at $x = 0$.
A planar shock propagating through the fluid ``b'' hits the corrugated
interface at $t = 0$.
Here the $x$- and $y$-axis are set to be perpendicular and parallel to
the shock surface.
The incident shock velocity is $-U_i \hat{x}$, where $\hat{x}$ is a
unit vector.
{\color{black}{Both the fluids}}
are stationary $\bm{v} = 0$ and have a uniform pressure $P_0$
before the shock passage.
The sonic Mach number of the incident shock is defined as $M = U_i
/c_{b0}$ where $c_{b0} = (\gamma_b P_0/ \rho_{b0})^{1/2}$ is the sound
speed of the fluid ``b''.
The physical quantities in the post-shocked region behind the incident
shock are calculated from the Rankine-Hugoniot conditions.
The interface has an initial corrugation of a sinusoidal form, $x =
\psi_0 \cos ( k y )$, where $\psi_0$ is the corrugation amplitude, $k =
2 \pi / \lambda$ is the perturbation wavenumber, and $\lambda$ is the
wavelength.

{\color{black}
Six non-dimensional parameters characterize the initial
configuration of the nonlinear single-mode analysis with a transition layer.
The Mach number $M$ parameterizes the incident shock velocity.
The contact discontinuity is expressed by the density jump
$\rho_{a0} / \rho_{b0}$ and the ratio of the corrugation amplitude
to the wavelength $\psi_0 / \lambda$.
The compressibility indicated by the
isentropic exponents $\gamma_a$ and $\gamma_b$ of each fluid is also an
essential element of this system.
Besides, we introduce a density transition layer with a
finite width of $L$, which provides an additional parameter of $L /
\lambda$.
In this analysis, we assume a constant value of $\gamma_a = \gamma_b =
5/3$ for simplicity.
Thus, the other four parameters ($M$, $\rho_{a0} / \rho_{b0}$, $\psi_0
/ \lambda$, and $L / \lambda$) are considered in the following.
}

Various shapes of the density distribution in the layer could be
plausible according to circumstances.
As a typical function, we take a hyperbolic-tangent function expressed
as
\begin{equation}
  \rho (x) = \frac{\rho_{a0} + \rho_{b0}}{2} \left[
  1 - A \tanh \left( \frac{2 x}{L} \right)  \right] \;,
  \label{eq:tanh}
\end{equation}
where $A = (\rho_{a0} - \rho_{b0}) /  (\rho_{a0} + \rho_{b0})$ is the
Atwood number.
Linear and exponential distributions are also examined for comparison,
which are given by
\begin{equation}
  \rho (x) =
  \left\{
  \begin{array}{lcl}
    \rho_{a0} & & \displaystyle \left(x \leq  -\frac{L}2 \right) \\
  \displaystyle \frac{\rho_{a0} + \rho_{b0}}{2} \left[
   1 - A \left( \frac{2 x}{L} \right)  \right] & &
    \displaystyle \left( |x| < \frac{L}2 \right) \\
    \rho_{b0} & & \displaystyle \left( x \geq \frac{L}2 \right)
  \end{array} \right.
  \label{eq:lin}
\end{equation}
and
\begin{equation}
  \rho (x) =
  \left\{
  \begin{array}{lcl}
    \rho_{a0} & & \displaystyle \left( x \leq - \frac{L}2 \right) \\
    \displaystyle \max \left\{ \rho_{a0} e^{
    - \frac1{L} \left| x + \frac{L}2 \right|} , \rho_{b0} \right\}
    & & \displaystyle \left( x > - \frac{L}2 \right)
  \end{array} \right. \;.
    \label{eq:exp}
\end{equation}
While the thickness of the transition layer is well defined by $L$ in
the hyperbolic-tangent and linear distributions, the effective thickness in
the exponential-type depends on the combination of the scale length $L$ and
density jump $\rho_{a0} / \rho_{b0}$.

There are several formulas suggested evaluating the linear growth
velocity of the RMI theoretically.
The linear growth with time, not exponential, is one of the unique
characteristics of the RMI.
Another feature of the RMI is that it occurs in both cases of
light-to-heavy ($\rho_{a0} / \rho_{b0} > 1$) and heavy-to-light
($\rho_{a0} / \rho_{b0} < 1$) configurations.

\citet{richtmyer60} was the first to study the problem of a planar
shock crossing the corrugated boundary between two fluids, and
proposed a generalization of the Rayleigh-Taylor formula as the growth
velocity
$\partial \psi /  \partial t = k v^{\ast} A^{\ast} \psi^{\ast}_0$,
where $v^{\ast}$ and $\psi^{\ast}_0 = \psi_0 ( 1 - v^{\ast} / U_i )$
are the zero-order velocity and the amplitude of the contact surface
just after the shock passage, respectively.
The Atwood number $A^{\ast} = ( \rho_{a}^{\ast} - \rho_{b}^{\ast} ) /
( \rho_{a}^{\ast} + \rho_{b}^{\ast} )$ is defined by the densities at
both sides of the post-shocked interface.
Then, \citet{meyer72} observed that the Ricthmyer prescription should be
modified using an averaged value between the pre- and post-shocked
interface amplitude, i.e., $\partial \psi / \partial t = k v^{\ast}
A^{\ast} ( \psi_0 + \psi^{\ast}_0 ) / 2$, in order to obtain agreement
between the numerical solution and the linear theory.
A similar heuristic approach was also proposed by
\citet{vandenboomgaerde98}.
Unfortunately, these empirical prescriptions are likely to fail for
high compressions \cite{vandenboomgaerde98}.

Further linear theories of the RMI have been done in the form of series
expansions in terms of inverse powers of the Laplace variable
\cite{fraley86}, in powers of the time \cite{velikovich96}, or in terms of
the Bessel functions \cite{wouchuk96,wouchuk97,coboscampos16,coboscampos17}.
In particular, the asymptotic growth velocity for both shock- and
rarefaction-reflected cases is calculated with the following
expression derived by \citet{wouchuk97}:
\begin{equation}
  v_{\rm wn} =
  \frac{- \rho_{a}^{\ast} \delta v_{ya}^{\ast}
        + \rho_{b}^{\ast} \delta v_{yb}^{\ast}}
       {\rho_{a}^{\ast} + \rho_{b}^{\ast}} +
  \frac{\rho_{a}^{\ast} F_a - \rho_{b}^{\ast} F_b }
       {\rho_{a}^{\ast} + \rho_{b}^{\ast}} \;,
\label{eq:dvi}
\end{equation}
where $\delta v_{ya}^{\ast}$ and $\delta v_{yb}^{\ast}$ are the initial
tangential velocities at both sides of the contact surface.
The quantities $F_a$ and $F_b$ represent the sonic interaction between
the contact surface and the transmitted and reflected wavefront,
respectively, which are proportional to the amount of vorticity left
behind the wavefronts in the bulk of each fluid.
For the case when a rarefaction is reflected, no vorticity is created
in the expanded fluid, i.e., $F_b=0$.

The Wouchuk-Nishihara (WN) formula is rigorously deduced from
linearized two-dimensional Euler equations after two wavefronts have
separated away from the interface.
The growth velocity given by Eq.~(\ref{eq:dvi}) is exact within the
limits of linear theory and inviscid flow.
It is valid for any initial configuration, and every element can be
analytically calculated from the pre-shocked parameters
\cite{wouchuk01a,wouchuk01b,coboscampos16,coboscampos17}.
The first term of the right-hand side of Eq. (\ref{eq:dvi}) is due
to the instantaneous deposition of the vorticity at the interface just
after the shock interaction.
On the other hand, the second term represents the interaction between
the contact surface and the wavefronts.
It becomes non-negligible for stronger shocks or highly compressible
fluids, and typically has the opposite sign to the first term.
The negative growth velocity stands for the phase reversal that could
occur the rarefaction-reflected cases.
Throughout our analysis, the WN formula $v_{\rm wn}$ is
used as the typical velocity of the RMI growth for a given set of
the parameters ($M$, $\rho_{a0} / \rho_{b0}$, and $\psi_0 / \lambda$).

We solve the system equations (\ref{eq:con})-(\ref{eq:ene}) in
two-dimension ($x$, $y$) {\color{black}{in the Cartesian coordinate system}}
by using a conservative Godunov scheme with the second-order accuracy in
space and time \cite{vanleer79,sano98}.
The exact solutions of the Riemann problem at each grid boundary are
used in the flux calculations for time integration of the variables
\cite{colella84}.
The scheme includes an additional numerical diffusion in the
direction tangential to the shock surface in order to care for the
carbuncle instability \cite{hanawa08}.
A periodic boundary condition is used in the
$y$-direction, and an
outflow boundary condition is adopted in the $x$-direction.
The size of the computational box in the $y$-direction
is always set to be $L_y = \lambda$.
The choice of $L_x$, on the other hand, depends on the
initial parameters.
The $x$-length is taken to be sufficiently extensive so
that both of
the transmitted shock and reflected shock (or rarefaction) never reach
the edge of the computational domain in all the runs.

Most of the calculations are performed with a standard resolution of
$\Delta_x$ = $\Delta_y$ = $\lambda/256$ unless otherwise stated.
The physical quantities are normalized by the initial density and
sound speed of the fluid ``b'', $\rho_{b0} = 1$ and $c_{b0} =
1$, and the wavelength of the surface modulation $\lambda = 1$.
The sound crossing time of the wavelength is also unity in our
normalization, $\lambda / c_{b0} = 1$.

\section{Numerical Results \label{sec3}}

\begin{figure*}
\includegraphics[scale=0.85,clip]{fig2.eps}%
\caption{
Spatial distributions of the density $\rho$ and the tangential
velocity $v_y$ at the nonlinear regime of the RMI growth $k v_{\rm wn}
t = 15$ for the cases of (a) $L / \lambda = 0.03$ and (b) $L / \lambda
= 3$.
The other parameters are identical for both cases, which are $M = 2$,
$\rho_{a0}/\rho_{b0} = 10$, and $\psi_0 / \lambda = 0.1$.
The $\tanh$-type transition layer is assumed.
The density distribution is depicted by the contour curves at the
levels from $\rho / \rho_{b0} = 6$ to 27.
The color map denotes the tangential velocity normalized by the growth
velocity of the WN model $v_y / v_{\rm wn}$.
The color-bar range of the velocity in (b) is $1/25$ of that in (a).
\label{fig2}}
\end{figure*}

First, we look at the difference in the density distribution caused by
the existence of a transition layer.
The growth of the RMI is usually recognized by the mushroom-shaped
elongation of the density interface.
Figure~\ref{fig2} shows the contour lines of the density at the nonlinear regime
of the RMI growth.
The horizontal axis $x$ is converted to a frame moving with the
contact-discontinuity velocity $v^{\ast}$ after the shock interaction.
The initial parameters in this fiducial run are the Mach number $M=2$,
the density jump $\rho_{a0}/\rho_{b0} = 10$, and the modulation
amplitude $\psi_0 / \lambda = 0.1$.
The function of the density transition layer is the hyperbolic tangent
given by Eq.~(\ref{eq:tanh}).
The snapshot is taken at $k v_{\rm wn} t = 15$, where $( k v_{\rm wn
})^{-1}$ is the unit timescale of the RMI.
The linear growth velocity of the WN model $v_{\rm wn}$ is evaluated
from Eq.~(\ref{eq:dvi}).
For the fiducial parameters, $v_{\rm wn} / c_{b0} = 0.20651$, so that
the RMI timescale corresponds to slightly shorter than the initial
sound crossing time, $( k v_{\rm wn} )^{-1} \sim 0.77 ( \lambda /
c_{b0} )$.

For a narrow transition case of $L / \lambda = 0.03$
[Fig.~\ref{fig2}(a)],
the RMI growth is nearly identical to the case with a sharp boundary
case ($L = 0$).
The width of the mixing layer defined
from the spike top to bubble bottom exceeds the modulation wavelength
of $\lambda$.
On the other hand, the deformation of the interface is significantly
reduced when the transition layer becomes comparable to $\lambda$.
Figure~\ref{fig2}(b) shows the density contours for a case of $L /
\lambda = 3$, in which the other parameters are the same as those of
Fig.~\ref{fig2}(a).
Although the location of the interface cannot be defined uniquely for
this case, the density contours are rather smooth compared to those in
Fig.~\ref{fig2}(a).
The fluctuation amplitude of the contour lines is at most a few times
larger than the initial corrugation amplitude of $\psi_0 / \lambda =
0.1$.
Thus, the transition layer indeed mitigates the growth of the RMI.
The enhancement of the modulation in the density structure is severely
suppressed.

Because the RMI growth is tightly connected to the tangential velocity
induced by shock interaction with a corrugated interface, we
focus on the $y$-component of the perturbed velocity in our
simulations.
Note that $v_y$ is nothing everywhere before the shock passage since
we consider homogeneous initial flow.
In Figs.~\ref{fig2}(a) and \ref{fig2}(b), the tangential velocity
$v_y$ normalized by $v_{\rm wn}$ is depicted by colors for each case.

The tangential velocity is of the order of $v_{\rm wn}$ when $L /
\lambda = 0.03$ [Fig.~\ref{fig2}(a)].
At the time of the snapshot $k v_{\rm wn} t = 15$, the fastest
velocity is localized at the roll-up region of the mushroom shape.
The mixing-layer width
due to the RMI motions
is still growing even at this nonlinear phase.
By contrast, the generation of $v_y$ is weakened by more than an order
of magnitude in the broad transition case of $L/ \lambda = 3$
[Fig.~\ref{fig2}(b)].
The color range of the tangential velocity in Fig.~\ref{fig2}(b) is
about $1/25$ of that in Fig.~\ref{fig2}(a).
Weak tangential shear is deposited in the middle of the transition
layer, where the most considerable distortion of the density contour
is observed.
The location of the maximum vorticity would be related to the largest
gradient of the density.

\begin{figure*}
\includegraphics[scale=0.85,clip]{fig3.eps}%
\caption{
(a)
Time evolutions of the maximum tangential momentum $|\rho v_y|$ in the
entire area of the computational domain for the cases of $L/\lambda =
0.03$ (black) and $L / \lambda = 3$ (red).
The other parameters are identical to the fiducial runs shown in
Fig.~\ref{fig2}.
The dependence on the density function is also indicated in this
figure by the different line types.
The results of the $\tanh$-type, liner-type, and $\exp$-type are depicted
by the solid, dashed, and dot-dashed curves, respectively.
The time in the horizontal axis is given in the unit of the RMI
timescale $( k v_{\rm wn} )^{-1}$.
(b)
Time histories of
the kinetic energy
defined by the tangential
velocity $E_{ky} \equiv \rho v_y^2 / 2$ integrated over the entire
domain.
The thickness of the $\tanh$-type transition layer is labeled for each
curve.
The other parameters are the same as those of the runs shown in (a).
\label{fig3}}
\end{figure*}

\begin{figure*}
\includegraphics[scale=0.85,clip]{fig4.eps}%
\caption{
(a)
Dependence of the mixing length $l_{\rm mix}$ caused by the RMI growth
on the thickness of the transition layer.
The mixing length is defined by the distance from the spike top to the
bubble bottom, which is evaluated through the tracer particle positions
at $k v_{\rm wn} t = 15$.
The simulation parameters are the same as those in the fiducial run
except for $L$.
The gray dashed line denotes the initial amplitude of $2 \psi_0 /
\lambda = 0.2$.
(b)
Standard deviation $\sigma$ of the interface velocities $v_x$ and $v_y$ in
terms of the layer thickness $L$.
The interface velocities are taken at $k v_{\rm wn} t = 15$ in the
same runs as in (a).
\label{fig8}}
\end{figure*}

The tangential velocity is a good indicator of the activity of the RMI.
The time evolutions of the maximum value of $| \rho v_y|$ for two cases
in Fig.~\ref{fig2} are shown by the solid curves in Fig.~\ref{fig3}.
The maximum momentum is divided by $(\rho_{a}^{\ast} +
\rho_{b}^{\ast}) v_{\rm wn}$ so that the vertical axis approximately
indicates the effective growth velocity relative to the original
$v_{\rm wn}$ of the WN model.
When the transition layer is narrow ($L / \lambda = 0.03$), the growth
velocity appears instantaneously at $t = 0$ and keeps nearly constant
around $\sim v_{\rm wn}$.
However, the growth velocity in the broader transition case ($L /
\lambda = 3$) increases gradually during the shock travels in the
smooth density distribution.
The peak value is much lower than the linear-theory prediction for
the discontinuous case.
Since the density changes continuously in the transition layer,
the shock pressure at the downstream, or the shock strength, is
weakened compared to the discontinuous case.
Such an effectively weaker shock causes a significant reduction of
the growth velocity of RMI in the linear phase \cite{wouchuk01a,wouchuk01b}.

The suppression effect due to non-zero $L$ seems to have little
dependence on the functional form of the density in the transition
layer.
The time histories of the maximum tangential momentum in the linear-type
[Eq.~(\ref{eq:lin})] and exponential-type [Eq.~(\ref{eq:exp})]
distribution are also plotted in Fig.~\ref{fig3}(a) by the dashed and
dot-dashed curves, respectively.
The difference in the density function is negligible if the layer is
much narrower than the modulation wavelength.
Huge decrease of the growth velocity $v_y$ is observed in all the cases
of $L / \lambda = 3$,
where the peak and asymptotic velocities are quite similar among the
different function cases.

The fluctuation kinetic energy
at the nonlinear regime of RMI may be a
useful quantity to evaluate the suppression effect by the transition
layer.
Figure~\ref{fig3}(b) shows the evolutions of the perturbed
kinetic
energy defined by $E_{ky} \equiv \rho v_y^2 / 2$ integrated over the entire
region.
The initial parameters are the same as in Fig.~\ref{fig2} except for
the thickness of the transition layer $L$.
As can be seen,
the fluctuation kinetic energy
decreases drastically if
$L/\lambda \gtrsim 1$.
When $L/\lambda = 10$, for example, the integrated $E_{ky}$ is reduced
by about three orders of magnitude compared to the sharp
transition case $L / \lambda \sim 0$.
In the $x$-direction, it is hard to define the perturbed velocity
because the unperturbed distribution is also time-dependent.
However, the $x$-component of
the perturbed velocity
must be comparable to that in the $y$-direction in the RMI motions.
Thus we believe that Figure~\ref{fig3}(b) is representing
the fluctuation kinetic energy
driven by the RMI properly.

The $L$ dependence shown by Figs.~\ref{fig3}(a) and
\ref{fig3}(b) are obtained by the simulations with the resolution of
$\Delta_x = \Delta_y = \lambda / 512$.
These results are found to be unaffected by the numerical resolution,
which is confirmed by identical calculations with different grid sizes
of $\lambda / 1024$ and $\lambda / 256$.
For the case of $L / \lambda = 0.01$, the transition layer is captured
by only five grids, so that its result would be regarded as that for
the discontinuous case.

Lagrangian tracer particles are often used to pursue the evolution of the interface shape and velocity distribution for the case of a sharp density jump.
Here we apply this method even for the cases with a finite transition layer.
The tracer particles are set initially at the center of the transition
layer, that is, along a line given by $x = \psi_0 \cos (k y)$ for all cases.
Mixing length $l_{\rm mix}$ is calculated from the difference between the maximum and minimum values of the $x$-coordinate among these particles.
Figure~\ref{fig8}(a) shows the characteristic mixing length by the RMI growth at $k v_{\rm wn} t = 15$ for various runs with different thickness of the transition layer.
The modulation amplitude at the nonlinear stage of the RMI has an apparent dependence on $L$.
For the case of $L/\lambda = 10$, the mixing length is almost the same as the initial modulation amplitude.
This fact indicates the severe suppression of the RMI due to the
transition layer, which is consistent with the result shown in
Figs.~\ref{fig2} and \ref{fig3}.

The perturbed velocity of the interface is inferred from the tracer particle velocities.
We can evaluate the standard deviation $\sigma$ of the interface velocity (or the velocity dispersion), which is shown in Fig.~\ref{fig8}(b).
Both components of $v_x$ and $v_y$ exhibit the same trend of the $L$-dependence, as seen in Fig.~\ref{fig8}(a).
Since the average velocity of $v_y$ is zero, the velocity dispersion $\sigma$ is identical to the root-mean-square of $v_y$.
If the thickness of the transition layer is negligible compared to the modulation wavelength, the perturbed velocity is comparable to the growth velocity of the WN model.
Although the velocity dispersion of $v_x$ in this limit is slightly larger than that of $v_y$, the difference is no more than double.
On the other hand, the unperturbed profile of $v_x$ in the transition layer depends on the position $x$.
Thus, the velocity dispersion may tend to be larger than the perturbed component alone, as the transition layer becomes thick.
This is another reason why we concentrate the $y$-component of the perturbed velocity.

\begin{figure}
\includegraphics[scale=0.85,clip]{fig5.eps}%
\caption{
Dependence of the integrated
kinetic
energy $\int E_{ky} dxdy$
measured at the nonlinear regime $k | v_{\rm wn} | t = 15$ on the
thickness of the transition layer $L$.
Various parameter runs listed in Table~\ref{tab1} are plotted with
different marks.
The meaning of each mark is described in the last column of
Table~\ref{tab1}.
The gray thick curve is the fitted function of all the data, which is
proportional to $[ 1 + ( qL / \lambda )^{p} ]^{-1}$ with $q = 2.11$
and $p = 2.46$.
\label{fig4}}
\end{figure}

\begin{table*}
\caption{
A list of the initial conditions for the simulations shown in
Fig.~\ref{fig4}.
The key parameters are the Mach number of the incident shock $M$, the
density jump at the contact discontinuity $\rho_{a0} / \rho_{b0}$, and
the modulation amplitude relative to the wavelength of $\psi_0 /
\lambda$.
Three types of the transition layer ($\tanh$, linear, and $\exp$) are
considered.
The linear growth velocity $v_{\rm wn}$ of the RMI is calculated based
on the WN model.
The obtained
kinetic
energy is fitted by $[ 1 + ( q L / \lambda
  )^{p} ]^{-1}$ as a function of $L/\lambda$, and the fitted results
for $q$ and $p$ are listed for each parameter set in the table.
A numerical factor $\zeta$ for each run is calculated
by solving appropriate Riemann problems.
The last column is the mark of the plot in Fig.~\ref{fig4} for each
case.
\label{tab1}}
  \begin{tabular}{cccccccccc}
  \hline \hline
  $M$ &
  $\displaystyle{\frac{\rho_{a0}}{\rho_{b0}}}$ &
  $\displaystyle{\frac{\psi_0}{\lambda}}$ &
  transition &
  $\displaystyle{\frac{v_{\rm wn}}{k \psi_0 U_i}}$ &
  $\displaystyle{\frac{v_{\rm wn}}{c_{b0}}}$ &
  $q$ &
  $p$ & $\zeta$ & mark \\ \hline
  2   & 10   & 0.1  & tanh   & 0.16433  & 0.20651  & 2.08 & 2.66 & 1.8 &
  black filled circle \\
  2   & 10   & 0.1  & linear & 0.16433  & 0.20651  & 1.87 & 1.89 & 1.8 &
  red plus \\
  2   & 10   & 0.1  & exp    & 0.16433  & 0.20651  & 3.90 & 1.84 & 1.8 &
  green cross \\
  1.2 & 10   & 0.1  & tanh   & 0.082788 & 0.062421 & 2.19 & 2.72 & 1.6 &
  blue square \\
  10  & 10   & 0.1  & tanh   & 0.18589  & 1.1680   & 1.58 & 2.79 & 2.0 &
  cyan square \\
  100 & 10   & 0.1  & tanh   & 0.18639  & 11.711   & 1.56 & 2.80 & 2.0 &
  yellow square \\
  2   & 3    & 0.1  & tanh   & 0.13365  & 0.16795  & 2.01 & 2.53 & 1.6 &
  red filled circle \\
  2   & 100  & 0.1  & tanh   & 0.081918 & 0.10294  & 2.56 & 1.73 & 2.0 &
  green filled circle \\
  2   & 0.3  & 0.1  & tanh   & $-0.20979$ & $-0.26364$ & 2.17 & 2.65 &
  1.1 &
  red open circle \\
  2   & 0.1  & 0.1  & tanh   & $-0.35302$ & $-0.44362$ & 1.92 & 2.77 &
  0.80 &
  black open circle \\
  2   & 0.01 & 0.1  & tanh   & $-0.44584$ & $-0.56026$ & 1.39 & 3.01 &
  0.34 &
  green open circle \\
  2   & 10   & 0.03 & tanh   & 0.16433  & 0.061953 & 2.16 & 2.63 & 1.8 &
  orange triangle \\
  2   & 10   & 0.3  & tanh   & 0.16433  & 0.61953  & 2.09 & 2.03 & 1.8 &
  purple triangle \\
\hline \hline
\end{tabular}
\end{table*}

It is found that the dependence of the RMI suppression on $L/\lambda$
is quite robust and valid for a wide range of the initial parameters.
The fluctuation kinetic energy
measured at $k | v_{\rm wn} | t = 15$ for
various cases listed in Table~\ref{tab1} are shown all together in
Fig.~\ref{fig4}.
Normalization of the
kinetic
energy in this diagram is to divide by
$( \rho_{a}^{\ast} + \rho_{b}^{\ast} ) v_{\rm wn}^2 \lambda^2 / 4$ that is
proportional to $v_{\rm wn}^2$.
It should be noted that the dimensionless linear growth velocity
$v_{\rm wn}/(k \psi_0 U_i)$ is determined by $M$, $\rho_{a0}/\rho_{b0}$,
and $\gamma_a=\gamma_b=5/3$ in our system.
For example, a higher Mach number gives a faster growth velocity so
that the normalization factor is larger for the higher $M$ case.
The growth velocity $v_{\rm wn}$ for each case is also listed in Table~\ref{tab1}.

All the data points in Fig.~\ref{fig4} exhibit a single
trend on $L / \lambda$, even though the vast parameter range of many
orders of magnitude are examined here.
The fiducial set of the parameters are chosen as $M=2$, $\rho_{a0} /
\rho_{b0} = 10$, $\psi_0 / \lambda = 0.1$, and $\tanh$-type function.
Then we examine the dependence of the transition function (linear- and
$\exp$-type), the Mach number ($M=1.2$, 10, and 100), the density jump
for shock-reflected cases ($\rho_{a0} / \rho_{b0} = 3$ and 100) and for
rarefaction-reflected cases ($\rho_{a0} / \rho_{b0} = 0.3$, 0.1, and
0.01), and the modulation amplitude ($\psi_0 / \lambda = 0.03$ and
0.3).
For each parameter case, we perform seven runs with different widths of
the transition layer in a range from $L / \lambda = 0.01$ to 10 to
identify the dependence.

When $L/\lambda \lesssim 1$,
the fluctuation kinetic energy
is flat and almost
identical to that in the discontinuous limit $L \rightarrow 0$.
On the other hand, if $L/\lambda$ becomes larger than unity, the
kinetic
energy decreases with a power law.
The dependence could be fitted by a function proportional to $[
1 + (q L / \lambda)^{p} ]^{-1}$ with two fitting parameters $q$ and $p$.
The fitted results for $q$ and $p$ are listed in Table~\ref{tab1} for
each parameter case.
The average values of all the cases are $q = 2.11 \pm 0.35$ and $p =
2.46 \pm 0.17$, which is drawn by the gray thick curve in
Fig.~\ref{fig4}.
Thus, the influence of the transition layer begins
to appear when $L \gtrsim \lambda / 2$.
In the limit of $L / \lambda \gg 1$,
the fluctuation kinetic
drops in
proportion to $L^{-5/2}$, which means the growth velocity has a
power-law dependence of $L^{-5/4}$ approximately.

\section{Discussion \label{sec4}}

Our numerical results suggest that the growth of the RMI is clearly
mitigated when the thickness of the transition layer becomes
comparable to the modulation wavelength.
Here we will consider the physical basis for this outcome.

The competition of two timescales reasonably evaluates the effect of
the transition layer.
One of those timescales is the transit time $\tau_{\rm tr}$ of the
incident shock to pass through the transition layer.
It is given by $\tau_{\rm tr} \equiv L / \langle U_i \rangle$ where
$\langle U_i \rangle$ is the averaged shock velocity in the transition
layer.
The other one is the stabilizing time $\tau_{\rm st}$ for the pressure
fluctuations by sound waves, which is expressed as $\tau_{\rm st}
\equiv \lambda / \langle c^{\ast} \rangle$.
Here $\langle c^{\ast} \rangle$ is the averaged sound speed at the
downstream of the shock.

When the transit time is shorter than the stabilizing time, the
transition layer has little effect on the growth of the RMI.
However, if $\tau_{\rm st} \lesssim \tau_{\rm tr}$, the RMI growth
should be modified by the presence of the transition layer.
Then the suppression condition is given by $L \gtrsim \zeta \lambda$,
where $\zeta \equiv \langle U_i \rangle / \langle c^{\ast} \rangle$.
We can guess the size of $\zeta$ assuming $\langle U_i \rangle \sim M
c_{b0}$ and $\langle c^{\ast} \rangle \sim ( c_{a}^{\ast} +
c_{b}^{\ast} ) / 2$, where $c_{a}^{\ast}$ ($c_{b}^{\ast}$) is the
sound speed of the post-shocked fluid ``a'' (``b'') at the interface
for the $L = 0$ case.
It turns out by solving appropriate Riemann problems that $\zeta$
is of the order of unity for most of the cases we examined
(see Table~\ref{tab1}).
Therefore the suppression condition is approximately given by
\begin{equation}
  \frac{\tau_{\rm tr}}{\tau_{\rm st}} \sim \frac{L}{\lambda} \gtrsim 1
\end{equation}
which is consistent with our numerical results.
Interestingly, this interpretation is independent of the density
gradient, which brings a difference from the stability condition for the
Kelvin-Helmholtz instability \cite{chandrasekhar61}.

If the transition layer is broader than the wavelength of the
interface modulation,
the kinetic energy of the RMI motions
decreases with the power of $L^{-p}$ where $p \sim 2.5$.
This result is equivalent that the growth velocity of the RMI is
reduced in proportion to $L^{-p/2}$ when $L \gtrsim \lambda$.
There might be several reasons for the suppression of the RMI due to
the density transition layer.

\begin{figure}
\includegraphics[scale=0.85,clip]{fig6.eps}%
\caption{
The linear growth velocity of the WN formula calculated from
Eq.~(\ref{eq:dvi}) shown as a function of the density jump $\rho_{a0} /
\rho_{b0}$ for various Mach number cases; $M = 1.2$ (red dashed), $2$
(black solid), $10$ (green dotted), and $100$ (blue dot-dashed).
The growth velocity is normalized by $k \psi_0 U_i$.
For the isentropic exponent, $\gamma_{a} = \gamma_{b} = 5/3$ is
assumed in all cases.
\label{fig5}}
\end{figure}

If $\tau_{\rm st}$ is shorter than $\tau_{\rm tr}$, the density
difference felt by the incident shock is smaller than the
discontinuous case, $\Delta \rho_0 \equiv |\rho_{a0} - \rho_{b0}|$.
The effective density difference is then estimated as $\Delta
\rho_{\rm eff} \sim \Delta \rho_0 \lambda / L$ assuming the linear
density gradient.
In a range of $0.01 \le \rho_{a0}/\rho_{b0} \le 100$ examined in our
analysis, the growth velocity has a complicated dependence on the
density jump \cite{wouchuk15}.
Figure~\ref{fig5} shows the growth velocity of the WN model as a
function of the density jump $\rho_{a0} / \rho_{b0}$ for different
Mach number cases.
In this figure, we assume $\gamma_a = \gamma_b = 5/3$ for the
isentropic exponent.
For the case of $\gamma_a = \gamma_b$, the growth velocity of the RMI
must be zero when $\rho_{a0} / \rho_{b0} = 1$.

In the limit of the small density difference $\Delta \rho_0 /
\rho_{b0} \ll 1$, the asymptotic linear growth velocity has a scaling law of
the form
\cite{coboscampos16,coboscampos17}
\begin{equation}
  \frac{| v_{\rm wn} |}{k \psi_0 U_i} \approx
  c_1^{s,r} \frac{\Delta \rho_0}{\rho_{b0}}
  + O \left( \frac{\Delta \rho_0^2}{\rho_{b0}^2} \right) \;,
\label{eq:vlim}
\end{equation}
where a coefficient $c_1^{s,r} (> 0)$ has different expressions for shock- or
rarefaction-reflected cases (see Appendix).
Replacing $\Delta \rho_0$ in Eq.~(\ref{eq:vlim}) with the effective
density difference $\Delta \rho_{\rm eff}$, the growth velocity in the
limit of $L / \lambda \gg 1$ is obtained by
\begin{equation}
\frac{| v_{\rm wn} |}{c_{b0}} \sim
2 \pi c_1^{s,r} M \frac{\Delta \rho_0}{\rho_{b0}}
\left( \frac{\psi_0}{\lambda} \right)
\left( \frac{L}{\lambda} \right)^{-1} \;.
\end{equation}
This relation suggests that the mitigation of the RMI is larger as the
transition layer
becomes broader, and which implies the qualitative coincidence with
the numerical results shown by Fig.~\ref{fig4}.

The physical reason behind the RMI suppression is that as the
transmitted shock advances through the transition layer, its ripple
decreases.
In the RMI, perturbations are generated as the result of the conservation of the tangential momentum across the fronts.
Thus, the smaller the shock ripple is, the weaker the perturbations are.
In the end,
the mixing motions
developed by the RMI is weakened due to the transition layer.
Likewise, weakened shock strength because of the smooth density
gradient promotes the suppression and affects the quantitative
dependence of the growth velocity.
Thus, the index $p \sim 2.5$ might be determined by the combination of
multiple origins, although the value seems to be valid in a wide range
of parameters.
Analytic study on the transition-layer effects would be challenging
future work but inevitable for further understanding.

In this work, we assume the isentropic exponent is constant everywhere $\gamma_a = \gamma_b = 5/3$.
The suppression due to the transition layer is affected by $\gamma$ through the stabilizing time $\tau_{\rm st}$.
Then, for a given thickness of $L$, the stiffer equation of state
would be easier to reduce the perturbed velocity of the RMI.

Lastly, we consider the application of our results for laboratory laser
plasmas.
The existence of a laser ablation plasma at a target surface could
play a role as a transition layer during shock interaction.
Exponential distribution of the density is often assumed for the
ablation plasmas.
Suppose a case of $\rho_{a0}/\rho_{b0}=0.01$, for instance, we need to
decide the interface density $\rho_{ai}$ as for the edge value of the
exponential distribution.
The interface density $\rho_{ai}$ would depend on the details
of the target density, laser intensity, and pulse shape so that it
has substantial ambiguity.

\begin{figure}
\includegraphics[scale=0.85,clip]{fig7.eps}%
\caption{
Time evolutions of the maximum tangential velocity in the exponential
transition layer for different interface density of $\rho_{ai} =
\rho_{b0}$ (red) and $\rho_{ai} = 0.1 \rho_{b0}$ (green).
The density jump is $\rho_{a0} / \rho_{b0} = 0.01$ and the scale
length is assumed as $L / \lambda = 10$ for both cases.
The other parameters are the same as in the fiducial run ($M = 2$ and
$\psi_0 / \lambda = 0.1$).
The time profile in the corresponding discontinuous case of $L = 0$ is
also shown by the black dashed curve.
(inset) Initial density profiles in the logarithmic scale for two cases
of $\rho_{ai} = \rho_{b0}$ (red) and $\rho_{ai} = 0.1 \rho_{b0}$
(green).
\label{fig6}}
\end{figure}

Then, we perform demonstrative calculations with different $\rho_{ai}$
in the suppression case of $L/\lambda = 10$, which is shown in
Fig.~\ref{fig6}.
This figure shows the maximum of the tangential momentum $|\rho v_y|$
searched from the entire domain for a given time.
The behaviors of the RMI are profoundly affected by the assumption of
$\rho_{ai}$.
Even if ten percent of the density jump exists, i.e., $\rho_{ai} = 0.1
\rho_{b0}$, the RMI growth in the $L/\lambda = 10$ case becomes as
active as the no-transition case.
In order to benefit from the stabilization by the
transition layer, the density distribution should be continuous from
$\rho_{b0}$ to $\rho_{a0}$.
This could be crucial in designing laser experiments for inertial
confinement fusion, where the elimination of the interfacial
instabilities is really demanded \cite{atzeni04,betti16}.

\section{Conclusions \label{sec5}}

We have investigated the role of the density transition layer on the
growth of the RMI
using two-dimensional hydrodynamic simulations.
{\color{black}{
Although three-dimensional evolutions of hydrodynamic instabilities
are essential in many cases, the two-dimensional study is still
important to understand the physics behind it.}}
A universal condition for the suppression of RMI due to the transition
layer has been obtained successfully through the systematic parameter study.
If the transition layer is narrower than the wavelength of the surface
modulation, the effect on the RMI is ignorable.
However,
the RMI growth
is severely reduced when the thickness
of the transition layer exceeds the modulation wavelength.
The obtained threshold condition, $L \gtrsim \lambda$, can be
explained by the comparison between the shock-transit time through the
transition layer and the stabilizing time of the pressure fluctuations
by sound waves.
This simple criterion will be useful to evaluate the importance of the
RMI in various situations, such as interstellar shock waves in
astrophysical phenomena and laser-driven shocks in inertial
confinement fusion experiments.

An exhaustive analytic study on the transition-layer effects should be
necessary. Nonetheless, the inclusion of compressibility effects and
double reflection of reflected waves makes the calculations extremely
cumbersome, and it is proposed as future work.

\begin{acknowledgments}
We thank K. Mima, K. Nishihara, H. Sakagami, Y. Sentoku and
J. G. Wouchuk for useful discussions and encouragement.
Computations were carried out on SX-ACE Lite at the Institute of Laser
Engineering, Osaka University.
This work was partly performed under the joint research project of the
Institute of Laser Engineering, Osaka University.
This research was supported by JSPS KAKENHI Grant No. JP26287147 and
No. JP19KK0072, JSPS Core-to-Core Program, B. Asia-Africa Science
Platforms No. JPJSCCB20190003, and MEXT Quantum Leap Flagship Program Grant
No. JPMXS0118067246.
F.C.-C. has received support from MINECO under Grant
No. ENE2016-75703-R, from JCCM Grant No. SBPLY/17/180501/000264,
and from BBVA Foundation Leonardo Grant No. 2019/00570/001.
\end{acknowledgments}

redpajama_set_name: RedPajamaArXiv


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text:
MoI Signs 20 Contracts on Second Day of ISNR Abu Dhabi 2016
391 Million Dirhams Worth of deals, Abu Dhabi, United Arab Emirates, The Ministry of Interior and the Abu Dhabi Police General Headquarters have signed AED 391,122,304 worth of contracts on the second day of the International Conference for Security and National Resilience (ISNR Abu Dhabi 2016). The announcement was made by Major General Ahmed Nasser Al Raisi, Inspector General of the Ministry of Interior and Deputy Chairman of the Higher Organizing Committee of ISNR Abu Dhabi 2016.
North Africa Commits to Homeland Security, with Defense Spending Growing to USD 31 Billion by 2020
Egypt to Post 12-18 Percent Annual Growth in Defense Spending: IHS; World's Largest Homeland Security and National Resilience Exhibition, ISNR in Abu Dhabi, Presents North African Business Opportunities in Emergency Preparedness, Cybersecurity, and Occupational Safety
World's Largest Homeland Security Event in 2016 Opens Next Week in Abu Dhabi
Held Under the Patronage of His Highness Sheikh Hazza bin Zayed, Abu Dhabi, United Arab Emirates. The world's largest homeland security and national resilience event in 2016, the 7thInternational Exhibition for National Security and Resilience (ISNR), opens next week at the Abu Dhabi National Exhibition Centre from 15-17 March 2016.
UAE Flag Formed of Largest Human Gathering
Abu Dhabi, United Arab Emirates: Major General Ahmed Nasser Al Raisi, Inspector General of the Ministry of Interior, Deputy Chairman of the Higher Organising Committee of International Exhibition for National Security and Resilience (ISNR 2016), witnessed on Sunday morning the breaking of the World Guinness record when the biggest ever UAE flag was formed by 3,929 persons.

redpajama_set_name: RedPajamaCommonCrawl


I was just looking at the pictures in Designing Web Usability, by Jakob Nielsen, as you do when its nearly time for a holiday. On page 243 is a screen grab of a Google search for the Gettysburg Address.
This was Google beta - and it returned a colossal 477 matches.
My Google - haven't you grown!


text:
Tyler Perry Delivers Inspiring Speech at People's Choice Awards: 'You're Worthy of Getting to Your Goal' [Video]
November 15, 2020 11:03 PM PST
Tyler Perry took to the stage to accept the People's Champion award at the 2020 People's Choice Award.
Tiffany Haddish did the honor of presenting the media mogul with the award, which he accepted with an inspiring speech.
via People:
"I'm so inspired and moved by this moment. I'm grateful. When I think about all these people, these underdogs, some former prisoners in jail for 20 years, one in jail for seven, they always inspire me," Perry said after he was surprised by the Tyler Perry Studios staff who appeared virtually before his speech. "So when this pandemic hit I knew I needed to do all I could to make sure they could continue in this great place that they're headed towards in their lives, in their marriages, businesses that they started for themselves, and their own companies and their houses, sending their kids to school."
The honor comes after Perry opened his own movie studio, Tyler Perry Studios, a 330-acre lot in Atlanta valued at $280 million where he films TV shows and movies, all of which he owns.
Also during his acceptance speech, Perry recalled a story about his encounter with an engineer who helped him dig a well at his Atlanta home. "Why am I telling you this, why am I talking about digging for water? In this world, we're all digging wells. In our lives, we're digging wells. We're digging wells in relationships, where we put all this time and effort and energy, and sometimes it doesn't give us what we need. We put all our time, energy and dreams in our business and it doesn't give us what we need or what we were after. But if you just keep digging, my God if you could just hear me right now, just keep digging," he said.
"You may be four inches away from every gift and every blessing that you ever wanted in your life. Had I given up, when I was homeless, when I was sleeping in my car, when I was hungry, had I given up, these people that you see on this screen right now would not be a part of my dream. There are people who are tied to your dream and your destiny, and you are worthy of getting to your goal. Keep digging, don't stop," Perry shared.
"When you get there, when you get to that water and you see it coming and you know what you need, this is what I always want you to remember, make sure everybody that you run into meets you at your worth," he concluded.
In September, Perry's fortune was officially set at $1 billion by Forbes. The outlet reported Perry has earned more than $1.4 billion in pretax income since 2005 and added him to the billionaire's list.
He joins other celebrities like close friend Oprah Winfrey ($2.5 billion), rapper and music mogul JAY-Z ($1 billion), Kanye West ($1.3 billion) and more. The list is currently topped by Amazon CEO Jeff Bezos, whose net worth is estimated at $205 billion, followed by Bill Gates, the co-founder of the Microsoft Corporation, at $94 billion
Watch Tyler's speech below.
Tags:Tyler Perry


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awesome image! congrats on being monthly featured artist for b/w, well deserved!
It is magical the way the blacksmith shapes glowing iron at the Moreston Heritage Village in southern Ontario. This is a fisheye lens view of the shop.


Palace opens to reveal 3 levels of play, lights, sounds and over 20 play pieces! Shimmer and Shine dolls are included!
Sound-activated! Kids can clap their hands to activate the lights, sounds and magic mirror! Over 100 phrases, sounds & songs!
Princess Samira appears in the magic mirror!
Decorate the palace with the included Genie Gems!


text:
Manar calls for more child abuse prevention services in rural Illinois
Published: Tuesday, March 26, 2019 02:30 PM
SPRINGFIELD – Illinois' primary child welfare agency is failing families in rural and downstate Illinois, State Senator Andy Manar said Tuesday.
"There is a void in services in parts of the state where child abuse is through the roof," said Manar, a Bunker Hill Democrat who chairs one of the Senate's two budget committees. "I believe DCFS is completely ill-equipped to handle what's happening in the rural parts of Illinois."
Manar's district includes rural communities where residents sometimes step in to help children in crisis because DCFS is unresponsive or services are unavailable, and large communities like Decatur, where in February 2-year-old Ta'Naja Barnes died from starvation, freezing and neglect by her mother and mother's boyfriend.
During a budget hearing Tuesday, Manar decried the absence of children's advocacy centers and other resources in every county of Illinois, even as there has been an increase in hotline calls and abuse investigations by the Illinois Department of Children and Family Services.
According to DCFS data, 39 accredited children's advocacy centers serve 95 of Illinois' 102 counties. For example, one center in Macoupin County serves families in Macoupin, Montgomery, Greene, Jersey and Calhoun counties.
Manar asked DCFS officials for more detailed information about the number and location of calls to the DCFS child abuse hotline, locations where abuse investigators work and more. He criticized DCFS for failing to make a sufficient budget request for the upcoming fiscal year that would allow it to properly serve the children and families of Illinois.
"I think we can all agree there's a crisis on our hands when it comes to many aspects of what DCFS is charged with doing. We recite the names of dead children in this hearing once a year," Manar said. "I want to know how much it's going to take the department to do the job that it's tasked with doing. If it's a big number, it's a big number."


David Coulthard wins the 2018 Race of Champions!
David Coulthard wins the 2018 Race of Champions at King Fahd Stadium in Riyadh, Saudi Arabia. The 46-year-old retired F1 driver defeated a big group of active racing aces from all over the world on his way to the second Champion of the Champions title. Previously, Coulthard won ROC Barbados event in 2014.
This time, Coulthard has won the winner's trophy in a fight against double World RX champion Petter Solberg. Two finalists were better than 'Mr Le Mans' Tom Kristensen and the 2017 World RX champion Johan Kristoffersson in the Semi-Final round.
"It's great to have been part of the first Race Of Champions here in Riyadh too. It's been a nice atmosphere and the people in the crowd have been treated to non-stop action. So thank you to Fredrik Johnsson and his team for yet another great event. To be honest, I'm always surprised when Fredrik invites me because I don't race any more, but I'm delighted when he does. The camaraderie with all the other drivers is special and we've had a wonderful welcome here," a delighted Coulthard said.
Twenty drivers participated in the main event of the 2018 Race of Champions. They raced against each other in a range of identical cars – including the Vuhl 05 ROC Edition, Ariel Atom Cup, Xtreme Pickup, Whelen NASCAR, KTM X-Bow Comp R and the ROC Car – on a purpose-built parallel track featuring ROC's iconic crossover bridge.
After Round 1 play-offs, sixteen drivers were split into four groups of four. Eight of them progressed into the knockout stages. In the quarter-finals, Kristensen avenged last year's Grand Final defeat by putting out the reigning ROC Champion of Champions Juan-Pablo Montoya.
Coulthard defeated 2014 Indianapolis 500 winner, Ryan Hunter-Reay. The 2017 IndyCar Champion Josef Newgarden crashed out to allow Kristoffersson an easy run through. Finally, Solberg defeated Sweden's FIA European F3 runner-up Joel Eriksson to complete the semi-final line-up.


Yup, the final month of partying for Party Season '09. With so many three-day weekends dis month (FOUR if ur from Selangor), it's gonna be unreal.
Some inexpensive booze always helps provoke the parties. Sid's Pubs has a promo all month – happy hours from opening (11am!) all the way till closing at Sid's Bangsar South & Sid's Kenny Hills.
At Sid's TTDI, its happy hours until closing specifically for Tiger & Guinness, also all-month. Niice.
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