[Introduction: Six decades into the nuclear age, it is worth reflecting on the fact that the United States remains the only nation to have detonated a nuclear weapon in combat, that Japan alone among nations has experienced nuclear attack, and that for all the terror unleashed in subsequent wars, no nation has launched nuclear weapons on an enemy since 1945. What forces have prevented nuclear war, and what lessons can be drawn from this experience for the future? Lawrence Wittner finds important answers to these questions in the world anti- nuclear movement.