The National Socialist German Workers’ Party almost died one morning in 1919. It numbered only a few dozen grumblers’ it had no organization and no political ideas. But many among the middle class admired the Nazis’ muscular opposition to the Social Democrats. And the Nazis themes of patriotism and militarism drew highly emotional responses from people who could not forget Germany’s prewar imperial grandeur. In the national elections of September 1930, the Nazis garnered nearly 6.5 million votes and became second only to the Social ....