Despite the development of a consensus foreign policy during the early years of the Cold War that supported containment of the Soviet Union, there were both internationalists and pacifists who opposed the efforts of the Truman administration. These groups felt that American actions, including the Truman Doctrine, the Marshall Plan, the North Atlantic Treaty, and even the Korean War weakened the UN, threatened the Soviet Union with war, hindered European economic recovery, and promoted colonialism. Often mislabeled as isolationists, both the pacifists, with their traditional opposition to...