1983 Soviet nuclear false alarm incident

On 26 September 1983, the nuclear early warning system of the Soviet Union reported the launch of multiple USAF Minuteman intercontinental ballistic missiles from bases in the United States. These missile attack warnings were correctly identified as a false alarm by Stanislav Yevgrafovich Petrov, an officer of the Soviet Air Defence Forces. This decision is seen as having prevented a retaliatory nuclear attack based on erroneous data on the United States and its NATO allies, which would have probably resulted in nuclear war and the deaths of hundreds of millions of people. Investigation of the satellite warning system later confirmed that the system had malfunctioned.

The incident occurred at a time of severely strained relations between the United States and the Soviet Union. Responding to the Soviet Union's deployment of fourteen SS-20/RSD-10 theatre nuclear missiles, the NATO Double-Track Decision was taken in December 1979 by the military commander of NATO to deploy 108 Pershing II nuclear missiles in Western Europe with the ability to hit targets in eastern Ukraine, Belarus or Lithuania within 10 minutes and the longer range, but slower BGM-109G Ground Launched Cruise Missile (GLCM) to strike potential targets farther to the east. In mid-February 1981, and continuing until 1983, psychological operations by the United States began. These were designed to test Soviet radar vulnerability and to demonstrate US nuclear capabilities. They included clandestine naval operations, in the Barents, Norwegian, Black, and Baltic seas and near the Greenland-Iceland-United Kingdom (GIUK) gap, as well as flights by American bombers, occasionally several times per week, directly to Soviet airspace that turned away only at the last moment.

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