Able Archer 83

Able Archer 83 is the codename for an annual command post exercise carried out in November 1983 by the North Atlantic Treaty Organisation (NATO). As with Able Archer exercises from previous years, the purpose of the exercise was to simulate a period of conflict escalation, culminating in a simulated DEFCON 1 coordinated nuclear attack. Coordinated from the Supreme Headquarters Allied Powers Europe (SHAPE) headquarters in Casteau, Belgium, it involved NATO forces throughout Western Europe, beginning on November 7, 1983, and lasting for five days.

The 1983 exercise introduced several new elements not seen in previous years, including a new, unique format of coded communication, radio silences, and the participation of heads of government. This increase in realism, combined with deteriorating relations between the United States and the Soviet Union and the anticipated arrival of Pershing II nuclear missiles in Europe, led some members of the Soviet Politburo and military to believe that Able Archer 83 was a ruse of war, obscuring preparations for a genuine nuclear first strike. In response, the Soviets readied their nuclear forces and placed air units in East Germany and Poland on alert. The apparent threat of nuclear war ended with the conclusion of the exercise on November 11.

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