(born 1955), US historian and writer. Among his books on the twentieth-century presidency are Mayday: Eisenhower, Khrushchev, and the U-2 Affair (1986), The Crisis Years: Kennedy and Khrushchev, 1960–1963 (1991), and The Conquerors: Roosevelt, Truman, and the Destruction of Hitler's Germany, 1941–1945 (2002).