Mussolini's march on Rome; Hitler's speeches before waves of goose-stepping storm troopers; the horrors of the Holocaust; burning crosses and neo-Nazi skinhead hooligans. Few words are as evocative, and even fewer ideologies as pernicious, as fascism. And yet, the world continues to witness the success of political parties in countries such as Italy, France, Austria, Russia, and elsewhere resembling in various ways historical fascism. Why, despite...