Cold War orthodoxy provides Americans with every reason to be proud of their "long twilight struggle" against Communism. It begins, of course, with Harry Truman, his heroic resistance to Soviet aggression in Europe, his defense of democracy in Korea and his opposition to the disastrous influence of McCarthyism, a malevolent force injected into "the bloodstream of the society" by the right in 1948. Moving on, orthodoxy teaches us of John Kennedy's doomed if honorable attempts to save an unsustainable ally in Southeast Asia, Lyndon Johnson's disastrous attempt to follow Kennedy's path and the...