Nuclear weapon

During the 1962 Cuban Missile Crisis, Soviet sub B-59 was hit by U.S. depth charges; its captain prepared a nuclear torpedo launch. All three senior officers had to agree, but Vasili Arkhipov alone refused. His no is credited with preventing Nuclear war.

In 1983, during the Cold War, a Soviet Union early warning system detected 5 US missile launches. Officer Stanislav Petrov judged it a false alarm — reasoning the US would launch everything if starting a nuclear war. He was right: the satellite had mistaken sunlight for launch flashes.