When Raul Castro decided to retire, both as leader of Cuba and head of the Communist Party last April, it was the end of a politically adventurous era for a country most American leaders loved to hate.In the late 1950s, it was Raul and his more famous older brother, Fidel Castro, who led an insurgency that toppled the American-backed dictatorship of Fulgencio Batista.Fidel was described as one of the last of the world’s die-hard socialists – and...