In the world’s collective consciousness, the word “Nazi” is synonymous with evil. It is widely understood that the Nazis’ ideology—nationalism, anti-Semitism, the autarkic ethnic state, the Führer principle—led directly to the furnaces of Auschwitz. It is not nearly as well understood that Communism led just as inexorably, everywhere on the globe where it was applied, to starvation, torture, and slave-labor camps. Nor is it widely acknowledged that Communism was responsible for the deaths of some 150 million human beings during the twentieth century. The world remains inexplicably indifferent and uncurious about the deadliest ideology in history. For evidence of this...