Nearly all of the Caribbean, Central America, and some Gulf ports in the United States depend on Venezuelan low-sulfur crude oil for their power plants, refineries, and balance-of-payments positions. Cuba is the most dramatic case of dependence: Without subsidized Venezuelan petroleum and the enormous sums paid for the Castros’ doctors – some excellent, some fraudulent – the island’s economy would sink, causing a wave of Cubans to leave, as has occurred repeatedly over the past half-century.