The nuclear weapons debate refers to the controversies surrounding the threat, use and stockpiling of nuclear weapons. Even before the first nuclear weapons had been developed, scientists involved with the Manhattan Project were divided over the use of the weapon. The only time nuclear weapons have been used in warfare was during the final stages of World War II when USAAF B-29 Superfortress bombers dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki in early August 1945. The role of the bombings in Japan's surrender and the U.S.'s ethical justification for them have been the subject of scholarly and popular debate for decades. Nuclear disarmament refers both to the act of reducing or eliminating nuclear weapons and to the end state of a nuclear-free world. Proponents of disarmament typically condemn a priori the threat or use of nuclear weapons as immoral and argue that only total disarmament can eliminate the possibility of nuclear war. Critics of nuclear disarmament say that it would undermine deterrence and make conventional wars more likely, more destructive, or both. The debate becomes considerably complex when considering various scenarios for...