The American Left used to lecture the nation about its supposedly paranoid suspicions of Russia. The World War II alliance with Joseph Stalin’s Soviet Union had led many leftists to envision a continuing post-war friendship with Russia. During the subsequent Cold War, American liberals felt that the Right had unnecessarily become paranoid about Soviet Russia, logically culminating in the career of the demagogic Senator Joe McCarthy. Later, in movies such as Seven Days in May, Doctor Strangelove...