It’s a slogan that’s long encapsulated the unique ability of Hugo Chávez’s fiercely nationalistic revolution to stay in power in Venezuela for 27 years: “United, we will win!” The young, the old, ruling party leaders and propagandists alike shout it at official events, street demonstrations and on state television, pumping their fists to show loyalty to the self-described socialist government — and its traditional antipathy toward the United States. Even when confronted with overwhelming truths