"Few things shocked the world more in the terrible month of June 1940 than seeing Marshal Philippe Pétain-a highly decorated hero of the first world war-shaking hands with Hitler. Pausing to look at the cameras, he announced that France would henceforth collaborate with Germany. "This is my policy," he intoned. "My ministers are responsible to me. It is I alone who will be judged by History." Five years later, in July 1945, Pétain was put on trial...

"The founding principles of the American Revolution-that all individuals have unalienable natural rights to life, liberty, and the fruits of their labor, and that governments should exist only to protect these rights-were a singularity in human history. The nation's failure to secure the slaves' equal rights to self-ownership led to a civil war and the constitutional recognition of this vital principle. And yet, scarcely four decades later, social...