At long last, Fidel Castro is dead. Now the oppressive system he installed in Cuba can wither and die, too — unless Donald Trump reverts to Cold War policies and gives Cuba’s failing dictatorship new life.

It is tempting to see Castro’s death as little more than a formality. After all, his brother Raúl has been running the country for nearly a decade, ever since ill health forced Fidel to step aside and kept him from reassuming command. But the very fact that Fidel still drew breath served as a limiting factor in the program of economic reform Raúl has been trying to enact.

According to The Post, Raúl Castro gave a speech in April in which he joked that “we have two parties here, just like in the United States — Fidel’s and mine.” Fidel’s is the Communist one, he added, “and you can call mine whatever you want.”

There is considerable truth in those words. Raúl has been trying to move his country toward the Chinese model of authoritarian one-party rule combined with some degree of free-market economic development. Fidel, a true believer in the brutal communist experiment, has consistently tried to slow, derail or reverse any meaningful economic change.

Fidel was reportedly appalled at the way Mao Zedong’s China was transformed by Deng Xiaoping’s reforms. He saw the society dividing into haves and have-nots. Worse, in his mind, he saw the Chinese Communist Party potentially sowing the seeds of its own demise by allowing the accumulation of private wealth and the development of civil society. He was determined that the Communist Party of Cuba would not make the same mistake.

Whether out of loyalty or obligation, thousands of Cubans filed past memorials to Fidel Castro. The Washington Post's Nick Miroff reports from Havana. (Nick Miroff,Jason Aldag/The Washington Post)

But the Cuban leadership no longer had a choice. Fidel barely managed to survive the collapse of the Soviet empire and the loss of huge subsidies from the USSR and Eastern Europe. Cubans were hungry in the mid-1990s, and there were violent anti-government riots, but “el Comandante” loosened strictures on private agriculture and enterprise — and then tightened them again as the crisis abated.

The Castro regime got another lifeline from Venezuelan strongman Hugo Chávez, whom Fidel cultivated as a protege. Chavez gave his mentor billions of dollars’ worth of oil, so much that the Cubans were able to satisfy their own needs and sell the surplus on the world market for precious hard currency. But Chavez died, Venezuela’s economy melted down, and the Castro regime found itself fresh out of saviors.

That explains Raúl’s willingness to work with President Obama to normalize relations. Those who complained that the United States didn’t “get more” in the deal fail to understand the reality of today’s Cuba. From their point of view, Cuba’s leaders were surrendering one of their primary instruments of power and control: the “threat” from Cuba’s hostile neighbor to the north.

For half a century, the Castros cited the U.S.-imposed trade embargo, the travel ban for U.S. citizens and other such measures as “proof” that the Cuban revolution was under sustained attack by the United States. From my experience — I’ve made 10 trips to Cuba and written a book about the place — most Cubans are not gullible; they see their government for what it is. But they are nationalistic. Even most of the brave dissidents who stood up to the Castro regime argued that hard-line U.S. policy was counterproductive, doing more to shore up the system than weaken it.

Raúl Castro knows he needs the economic boost that an opening to the United States will produce. But the price he is paying — allowing more free-market economic development, permitting freer access to the Internet, letting more Cubans have smartphones — will make any return to a “purer” form of communism impossible.

That’s where things stand now, and Fidel’s death should hasten change on the island. Unless a certain president-elect does something tragically dumb.

“If Cuba is unwilling to make a better deal for the Cuban people, the Cuban/American people and the U.S. as a whole,” Trump tweeted Monday, “I will terminate deal.”

I’m betting that no one, including Trump, knows exactly what that means in concrete policy terms. But we do know that now, for the first time since the Kennedy administration, we have the chance to flood Cuba with American ideas and values. That is how we promote freedom.

If Trump goes back to a posture of implacable U.S. hostility, he will disappoint and discourage millions of Cubans while strengthening the hand of only one: Raúl Castro, who will be all too happy to play David to Trump’s Goliath.

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