Support for Havana from the regime in Venezuela, another target of the Trump administration, has been halted, compounding Cuba’s economic troubles.

Shortly after he was inaugurated as president of Venezuela in 1999, Hugo Chávez, threw the struggling Cuban economy a lifeline, sending 100,000 barrels of oil a day, half of which the Cuban government sold on the world market for hard currency. As partial payment for the cheap oil, Cubans provided intelligence and military support to Mr. Chávez and to his successor, Nicolás Maduro, to help them consolidate their corrupt, autocratic project.

But as Venezuelan oil production plunged in recent years, and global prices fell, Cuba’s life-support system dried up to between 20,000 and 50,000 barrels per day, as of April.

The Trump administration has seen the weakness of these two economies as an opportunity to push for regime change in both countries.

The first target was Mr. Maduro, hoping his fall would bring democracy to his country and thus bankrupt the Cuban regime, finally bringing it to its knees. Now, as administration officials face their failed, overhyped efforts to topple Mr. Maduro, they have changed their focus: they are blaming Cuba for Mr. Maduro’s survival — rather than Mr. Maduro for the Cuban government’s survival.

Cubans — and the Cuban leaders — have been through worse. American restrictions on trade and travel to Cuba are minor compared to the difficulties they faced after the collapse of the Soviet Union, during which the Cuban economy contracted by more than one third. Even then, with food, electricity and hope all in short supply, the Castro government survived.

Today, Cuba’s leadership, under Raúl Castro’s handpicked successor, Miguel Díaz-Canel, is once again rallying the island nation’s citizens to tighten their belts, for example by promoting hutia, a local rodent, as a source of protein. And other authoritarian powers, like China and Russia, are more than willing to throw even just a bit of economic help, and lots of anti-American ideological support, which didn’t exist during the post-Cold War period.

The Trump administration’s strategy will fail, as it has in the past, and ordinary Cuban citizens will continue to bare the brunt of a misguided American policy. When will American leaders finally learn the lessons of history?

Christopher Sabatini, a lecturer at Columbia University’s School of International and Public Affairs and a nonresident fellow at Rice University’s Baker Institute, is executive director of Global Americans, a think tank.

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