Cubans are struggling with blackouts and fuel rationing amid President Trump’s campaign to provoke regime change by choking off the energy supply of the island nation, which is heavily dependent on fuel imports. Trump last month threatened to impose tariffs on any country that sends oil to Cuba, labelling the island “an unusual and extraordinary threat” to U.S. national security. He noted the Cuban government’s relations with Russia, China, and Iran as evidence of that threat, which, Trump suggested, would present as “migration…