When most Americans think of the Constitution, they undoubtedly think of the rights provisions — primarily the Bill of Rights and the 14th Amendment, with its guarantees of "equal protection" and "due process of law." One need not denigrate those in order to point out that in many ways the most important features of the Constitution are those we rarely think about, in part because they never lead to court challenges. These are the structural provisions of the Constitution, designed in 1787 and, remarkably, unamended since then. They tend to be as little noticed as the air we breathe, and just as essential.

For all of the concern this presidential election has justifiably generated about the degree to which cherished rights might be vulnerable, it also highlights the importance of the structural provisions. One simply cannot understand what is at stake without paying attention to them — and to their consequences for our lives in 2016.

Take the presidential system itself. This year will be remembered for the Trump insurrection, but it should also remind us of the vulnerability of a system that includes an independently elected president with remarkable power. Regardless of who wins, this year’s political developments should lead us to reflect on the flaws of the presidency, and of related constitutional provisions.

Our failure to address structures leads us to a dangerous overpersonalization of politics – particularly presidential politics. As the great German sociologist Max Weber predicted about a century ago, the American version of presidentialism contains within it the seeds of a dangerous Caesarism, the yearning for a Great Man (or, now, Great Woman), who promises to take control of a dangerously gridlocked and malfunctioning political system and impose his or her own vision on it.

That, of course, was a central theme of the campaigns of both Donald Trump and Bernie Sanders. Both ran as "disrupters"; Sanders described himself as the leader of a "political revolution." That their policy proposals often made relatively little sense, in part because there was no plausible path to congressional passage of the necessary legislation, was almost irrelevant.

The presidential system makes outsider candidates, and messianic candidates, possible

Sen. Sanders, as we know, was ultimately unsuccessful, not least because the Democratic race quickly turned into a two-candidate contest, giving the better-known, party-approved candidate an advantage.

Donald Trump was far luckier: He began in an unprecedented 17-candidate race with unparalleled name recognition and the ability to play to the media and to the Fox Television audience. As CBS executive Leslie Moonves said, Donald Trump "may not be good for America, but [he’s] good for CBS" — in terms of ratings and advertising revenue. And Trump, whose approximately 14 million total primary votes represented only 44.9 percent of the total Republican primary vote, was able to prevail against a notably disorganized and maladroit team of rivals.

Trump is almost certainly the most ominous major party candidate in our history. But one should note that his campaign could be viewed as its own version of Barack Obama’s 2008 campaign, which was organized around the theme of "the audacity of hope." Obama, too, pledged a transformative politics, often short on details and long on charisma. Not surprisingly, he did not achieve the kind of transformation many of his supporters were hoping for.

Today, many of Trump’s supporters, including at least some who voted for Obama in 2008 and possibly even in 2012 (against a Republican candidate who exhibited no concern at all for the plight of the working class), are tempted by a new "disrupter." Their alienation from a gridlocked status quo has made them all too willing to overlook some of the obvious problems with Trump as an actual president.

Some of Trump’s more tepid "supporters," notably those callow Republican officials who say they will vote for him without actually endorsing him, go on in effect to celebrate the US Constitution by promising that it offers ample ways to "check and balance" any presidential excesses. Think only of House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell.

But there are elements of whistling past the graveyard in such pronouncements. Among other things, they requires that one ignore the vast powers that have accreted to the White House since World War II with regard to military and foreign policy, not to mention various ways that presidents of both parties have been happy to push the envelope with regard to assertions of executive authority over administrative agencies. In any event, one can be confident that most of those who genuinely support Trump are not devotees of checks and balances (save with regard to a Clinton presidency).

Presidents get far more power than prime ministers — and you can't fire them

The problems with presidentialism only begin with the method of selection, including, of course, the Electoral College; they continue after the winner takes office. Consider that the person inaugurated on January 20 will have a guaranteed four-year tenure in office until January 20, 2021 — save for the wild card of impeachment, which has proven to be quite weak as a practical matter. There is no mechanism for "firing" a president, even if the country, including Congress, loses faith in his or her judgment, including in matters of literally life-and-death importance.

Unless a president commits a "high crime and misdemeanor" (whatever exactly that might be is a matter of endless argument), he or she remains secure in office, with all of the legal powers of the position. This includes the entitlement to serve as "commander in chief" of the armed forces, and the power to withdraw, without congressional consent, from what might be thought to be solemn treaty commitments.

The "winner-take-all" feature of presidentialism exacerbates the problem of presidential power. The winning candidate basically has a free hand in selecting the Cabinet and filling many other public offices, including the federal judiciary. This is true even if he or she received far short of a majority of the popular vote, as was the case with Richard Nixon in 1968 and Bill Clinton in 1992, each of whom received only 43 percent of the popular vote. (The 2000 election, where the winner of the popular and electoral votes diverged, presents a quite different problem.)

There is, of course, the reality of Senate confirmation, which on occasion might check presidential power. Should the Democrats regain the Senate next month, we shall see if they will acquiesce in retaining the filibuster regarding Supreme Court nominations or — given the otherwise sober John McCain’s threat to reject all of Clinton’s nominees — simply abolish it and thus, as a practical matter, give President Clinton enhanced power to pack the Supreme Court, and the rest of the federal judiciary, with nominees who share a broadly liberal vision of the Constitution. (The Democrats took a similar course in 2013 regarding all nominations to what the Constitution calls the "inferior" federal courts.)

Parliamentary systems, in contrast, often feature coalition governments, even "governments of national unity," that apportion cabinet and other positions among the otherwise conflicting political parties who have agreed to come together in a governing coalition.

Presidents have no incentives to cooperate with an oppositional Congress (and vice versa)

Benjamin Wittes, of the Brookings Institution, has suggested that Secretary Clinton commit herself to a "government of national unity" by pledging to appoint a significant number or Republicans to her Cabinet. Such calls from the would-be sensible center are a quadrennial tradition. But even were she to do so — and pay whatever attendant costs might be imposed by an ever-more-liberal Democratic Party eager to govern again (especially if the Senate and House should turn Democratic) — such a government might well founder on the unwillingness of House or Senate Republicans to join in the warm glow of unity. This would be an especially important problem, to say the least, if the House should remain Republican, as is still predicted.

There is a relatively simple structural explanation for the unlikelihood of a genuine kumbaya moment even if a President-elect Clinton wanted one. Our constitutional system focuses attention on a single individual, the president, who is, correctly or not, praised or blamed for what occurs in the wider polity during his or her term in office. A first-term incumbent who presides over (and gets credit for) what is thought to be progress will be rewarded by reelection. Perceived failure, on the other hand, is likely to lead to ouster.

An opposition party that contributes to genuine achievements may find itself, in effect, helping to reelect the incumbent. Thus, in 1996, it was Newt Gingrich who immeasurably aided Bill Clinton’s reelection efforts by giving him a "welfare reform" bill that he in fact signed; Bill Clinton then immediately took credit for "ending welfare" as we had known it.

Republicans might have hoped that Clinton would not call their bluff and that Bob Dole would have a winning campaign issue. But Clinton did call their bluff by signing the bill, and Dole’s campaign simply collapsed. Similarly, in 2004, Edward Kennedy contributed immensely to George W. Bush’s successful campaign for a second term by working with Bush on his two signature domestic issues, No Child Left Behind and the prescription drug bill.

So when McConnell, the Senate Republican leader, announced that his primary goal was to deny President Obama a second term, a move that appalled good-government types, he was simply saying that he was part of the opposition party. His behavior in attempting to deny Obama any significant accomplishments was altogether rational from the narrow perspective of the interests of the Republican Party.

One can expect a similar strategy should Secretary Clinton become president. Already, Republicans are lining up to run against Clinton in 2020. Even if she proclaims her devotion to a "government of national unity," why in the world would one expect congressional Republicans to cooperate by helping to pass any signature programs if the likely outcome would be Clinton’s reelection in 2020?

The potency of the veto power is overlooked

And what if Clinton — currently at least a 90 percent favorite in most presidential polls — wins but both the Senate and House remain Republican? One might well expect the first act of the Republican Congress to be the passage of legislation repealing Obamacare, and the first act of the Democratic president to be vetoing the legislation.

Clinton will win that battle for the simple reason that it takes a two-thirds vote of each house of Congress to override a presidential veto. For that reason, it’s not surprising that presidents have won approximately 95 percent of all veto battles — not to mention the fact that the very threat of a veto can be very important in molding legislation while in Congress.

Taking the veto power into consideration, it could be argued that in important ways we have a tricameral legislature, and not merely a bicameral legislature. Will a President Clinton be able to gain her nominees seats on the federal judiciary, including the Supreme Court, should the Senate remain Republican? Who knows, given that a Republican Senate wouldn’t even have to filibuster. They may, in the case of Judge Merrick Garland, refuse to hold hearings or, following perfunctory hearings, simply vote to reject any of Clinton’s nominees.

The twin problems of presidential overreach and political gridlock have structural roots. Yet it is virtually taboo to bring up, in mainstream discourse, any of the distorting aspects of our governmental structure. No one has asked either of the candidates, for example, if they think the United States might be better off with a parliamentary system of government. Most people — and certainly all mainstream journalists — would regard it as bizarre to waste valuable time during a debate to discuss such a hypothetical.

It is quite easy to portray Trump as an "anti-constitutional" candidate. It can well be doubted that he has ever seriously read or thought about the document, and he exhibits dangerously dictatorial tendencies that we hope are precluded by the Constitution. But we should realize that his candidacy also tells us things we might not wish to hear about the Constitution and its political order in the 21st century. In his own way, he may be the canary in the coal mine, and the question is whether we will draw the right lessons from his improbable candidacy and his apparent ability to garner the votes of at least 40 percent of the American public.

Sanford V. Levinson is a professor of law and government at the University of Texas Austin. His books include Framed: America's 51 Constitutions and the Crisis of Governance and An Argument Open to All: Reading 'The Federalist' in the 21st Century.