US-Cuba deal has vocal critics
The news that the US plans to normalise relations with long-time Caribbean thorn-in-the-side Cuba caught much of Washington off-guard.
For supporters the announcement was greeted with excitement and a certain amount of "it's about time" exasperation.
The Cuban embargo, writes Vox's Matthew Yglesias, is the "longest-running joke in American foreign policy, and something that can't come to an end a moment too soon".
"Designed over 50 years ago to somehow try to starve the Cuban population into overthrowing the Castro regime, it has failed, disastrously, and somehow allowed Cuban communism to outlive its Soviet sponsor by a generation," he writes.
Many pundits argued that US Cuban policy had long been dictated by a small, yet vocal community of Cuban expatriots in Florida. President Barack Obama's announcement, they contend, is a signal that the broader but more diffuse interests of the US as a whole may finally be recognised.
"Why does Obama think he can beat the Cuba lobby now?" asks Bloomberg View's Noah Feldman. "The accidental political configuration of the moment provides the best explanation."
He says Mr Obama no longer has to worry about re-election, it's two years before congressional Democrats face voters and if former Florida Governor Jeb Bush ends up as the Republican 2016 presidential candidate, Florida won't be a battleground presidential state.
The view that improved relations with Cuba was a needlessly delayed, yet welcome development was challenged on a number of different fronts, however.
In official Washington, Florida Senator Marco Rubio has been one of the most active voices decrying the deal. On Thursday he took to the pages of the Wall Street Journal to argue that Mr Obama has offered a financial lifeline to the island without achieving any significant concessions in return.
"Reasonable people can disagree about the efficacy of American foreign policy toward Cuba and even the embargo, but no serious person can argue that the manner in which President Obama unilaterally granted concessions to the regime in Havana was well advised," he writes.
The Washington Post's Dana Milbank calls Mr Rubio's statements an "emotional - and at times inaccurate" response to abandoning a "vestigial policy that has stopped serving a useful purpose".
He might also want to have a few words with his paper's editorial board, which says Mr Obama's action is an "undeserved bailout" for Cuba's communists.
Things were looking grim for the Castros, they write, with the economies of their Russian and Venezuelan supporters tanking due to low oil prices and a population making growing demands for human rights.
The influx of hard currency from US investment, they say, will allow the communist leaders to weather the storm.
The sanctions, they write, had marginalised Cuba in the Western Hemisphere. Lifting them, they continue, will likely help Cuba become another Vietnam - where "a flood of US tourists and business investment" has allowed a totalitarian system to make no improvement in human rights.
"Mr Obama may claim that he has dismantled a 50-year-old failed policy; what he has really done is give a 50-year-old failed regime a new lease on life," they conclude.
Other critics fear that improved relations with Cuba may not lead to improved conditions for Cubans - and may weaken perceptions of the US in other areas of the globe.
The Federalist's Sean Davis says he wants to believe the claims that free and open trade will liberalise Cuba, but he's not optimistic.
The reason, he says, is there are currently two currency systems in the island nation - one based around the US dollar for tourists and the elite and a peso system for ordinary Cubans.
"The result of the Cuban two-currency economy - one of which is forbidden to its people - is that every dollar will eventually find its way into the hands of the Cuban government," he writes.
Increased US investment doesn't mean things will get better for the average Cuban, he concludes, it just means the government will get wealthier. Until the Cuban peso can be freely traded, the Cuban people won't be free.
Elliott Abrams, who served in foreign policy posts in multiple Republican administrations, writes in the Weekly Standard that the Cuban move should concern US allies in the Middle East, Asia and Europe, who will wonder if the US will someday announce a "major policy shift" toward other regional provocateurs, such as Iran, China and Russia.
"What are American guarantees and promises worth if a 50-year-old policy followed by Democrats like Johnson, Carter and Clinton can be discarded overnight?" he asks. "In more than a few chanceries the question that will be asked as this year ends is 'who is next to find that America is today more interested in propitiating its enemies than in protecting its allies?'"
In his Wall Street Journal piece, Mr Rubio says that he will do "everything in my power" to block Mr Obama's Cuban policies in Congress. And given that Congress must approve any easing of the US embargo, his threat has teeth.
In public statements, he's also threatened to block the confirmation of a US ambassador to Cuba and prevent funding for construction of a US embassy in Havana.
While Mr Obama's move has both symbolic and diplomatic importance, Congress can exercise considerable power over just how long-lasting and broad the rapprochement becomes.
Even those who support Wednesday's news have expressed some concern that any liberalisation in Cuba must be done in a careful, controlled manner, lest oligarchs and corruption replace dictatorship.
"Many past attempts at rapprochement between the United States and Cuba have failed miserably, as have efforts to transform the relationship," writes the Atlantic's Adam Chandler.
While the end of the US-Cuba "Cold War-legacy stalemate" would be a historic achievement for the president, he says, "let's not start celebrating yet."
Given the range of opponents who have come forward to criticise the president's announcement, his words may ring true.