Exercise Able Archer

Exercise Able Archer was an annual exercise by the United States Military in Europe that practiced command and control procedures, with emphasis on transition from just convention operations to chemical, nuclear, and conventional operations during a time of war. When it was active, it was seen as the culmination of Exercise Autumn Forge. The exercise is best known for Able Archer 83, which nearly started a nuclear war with the Soviet Union.

The exercises themselves simulated a period of conflict escalation, culminating in a simulated DEFCON 1 coordinated nuclear attack.

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