With his legacy in mind,
He ended a Cold War animosity that had begun before he was born and established unprecedented diplomatic, economic and cultural ties with a Communist-ruled island long off-limits to most U.S. citizens.
Trump may have signaled a shift in his hard-line stance when he said it was his "hope that today marks a move away from the horrors endured for too long, and toward a future in which the wonderful Cuban people finally live in the freedom they so richly deserve."
As a candidate, Trump variously threatened to scuttle Obama's changes — especially when he was campaigning among anti-Castro Cuban immigrants in Florida — or to seek what he calls a better deal.
The question is, as Cuba expert William LeoGrande at American University in Washington put it: Will Cuba policy meet Trump the hard-liner or Trump the deal-maker?
Trump's selection of a secretary of State, still very much up in the air and reportedly roiled by disagreement within the transition team, may give a sense of how much he will try to change policy toward Cuba.
Some reversals, from a legal and technical standpoint, would be easy. Obama enacted many of the new measures through executive authority and once he's in the White House, Trump can overturn those with his signature.
Obama recently used executive action, for example, to expand the legal importation of Cuban cigars and rum by U.S. citizens who visit the island. Obama also vastly increased the number of Americans who can visit, and U.S. businesses that can work on the island.
But there is also pressure from U.S. agriculture and tourism sectors to continue with the more relaxed regimen for doing business. With flights and cruise ships pouring into Cuba daily, the country is proving a wildly fertile new market.
Trump the hard-liner spoke first in his statement Saturday.
"A brutal dictator" has died, Trump said, citing what he called Castro's legacy of "firing squads, theft, unimaginable suffering, poverty and the denial of fundamental human rights."
Trump went on to praise the support of the Cuban-American group of veterans who fought in the failed CIA-backed attempted invasion of the Bay of Pigs in 1961. The episode has been considered a fiasco for U.S. policy ever since.
But then Trump suggested that Castro's death marked a turning point and opened a future in which Cubans "can finally begin their journey toward prosperity and liberty."
Castro's brother Raul, the current president, is also a communist and an old-school military man. But Raul, 85, has already said he will step down in 2018, so Trump presumably won't have to deal with him for very long after he enters the White House.
Whatever direction Trump chooses, he is unlikely to try to reimpose the complete diplomatic and economic isolation of Cuba even if he revokes some of Obama's executive actions.
After decades of pent-up demand, the number of U.S. tourists to Cuba grew 80% this year compared with 2015. Hundreds of commercial flights go to and from the island weekly, with U.S. carriers scheduled to join this week.
Other tourism industries, including in-home lodgings, restaurants and banking services with U.S. credit cards — unheard of until now — are flourishing.
Agriculture businesses, including chicken and pork suppliers in the southern United States and farm-equipment companies in the Midwest, are eagerly pursuing prospects.
The business community will undoubtedly make its position heard as the president-elect ponders what to do in Cuba.
"There is going to be a strong push back," said Eric Olson, associate director of the Latin American program at the nonpartisan Woodrow Wilson International Center for Scholars in Washington. "Trump is after all a hotel man. I suspect he will understand the potential for American enterprise."
In deciding to restore ties with Cuba, Obama made several calculations.
A half-century-old policy of isolation, embargo and sanctions had clearly not weakened the Castro brothers' hold on power. Many would argue that it backfired.
Obama also decided that waiting for reciprocal action from Havana was holding his decisions hostage to what the Castro government might or might not do.
Ultimately, he decided, engaging with Cubans, first, and Cuba second would spread a desire and impetus for freedom, ignoring whether President Castro acted in kind.
After two years of secret negotiations, facilitated in part by Pope Francis, Obama and Raul Castro announced a renewal of diplomatic ties in December 2014. Within a year, the countries had reopened their embassies and expanded trade and travel. This year, Obama traveled to Havana, the first sitting U.S. president to do so in nearly 90 years.
Obama's next step was to push the policy as far as he could. He could not end the trade embargo put in place under the Eisenhower administration. Only Congress could do that, and a handful of Cuban-American legislators continued to block that path.
Instead, Obama ordered changed hundreds of regulations that, in the words of his national security advisor,
"It would be profoundly unwise and counterproductive to turn back the clock," she said in October.
Obama and advocates of the thaw with Cuba note that public opinion in the U.S. has also shifted. New opinion polling indicates overwhelming approval for detente among Cuban-Americans, traditionally anti-Castro but now infused with younger blood.
"The death of Fidel Castro will make it more difficult to justify policies that are rooted in past ideologies rather than future opportunities," said Geoff Thale, program director for the Washington Office on Latin America, a nonpartisan think tank.
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