The membership of the Communist Party of the United States (CPUSA) never reached 100,000 at any one time, but the party nonetheless has attracted an extraordinary amount of scholarly attention over the years. Hundreds of books and thousands of articles have been devoted to the CPUSA's activities. No political movement in U.S. history has been the subject of such frequent congressional investigations and hearings or faced more sustained attack by government agencies. The opposition to Communism during the Cold War was, arguably, more widespread and intense than Communism itself.
One portion of this deep-seated anti-Communism has obsessed scholars. Senator Joseph McCarthy leaped into national prominence in 1950 when he launched an attack on Communists in government. Just four years later, he was censured by his Senate colleagues. The McCarthy phenomenon—and studies of his alleged precursors and aiders and abettors (Martin Dies, J. Edgar Hoover, the House Un-American Affairs Committee)—have been...