Able Archer 83 was a five-day NATO military exercise held in November 1983 that simulated a period of escalating nuclear conflict, culminating in a simulated DEFCON 1 coordinated nuclear strike. It was dangerous because Soviet intelligence, already primed to watch for signs of a U.S. first strike under Operation RYaN, interpreted several unprecedented features of the exercise as indicators of a genuine attack, leading the Soviet military to load nuclear warheads onto bombers and place air units in East Germany and Poland on alert.
When did Able Archer 83 take place and how long did it last?
Able Archer 83 began on the 7th of November 1983, and concluded on the 11th of November 1983, lasting five days. It was part of an annual NATO exercise series and was coordinated from the Supreme Headquarters Allied Powers Europe at Casteau, Belgium.
Who was Stanislav Petrov and what did he do during the Able Archer 83 period?
Lieutenant Colonel Stanislav Petrov was a Soviet officer on duty on the night of the 26th of September 1983, when the Soviet orbital missile early warning system reported an intercontinental ballistic missile launch from U.S. territory. He dismissed the warning as a computer error, and later dismissed four additional reported launches for the same reason. A subsequent investigation confirmed all five alerts were false alarms caused by a rare alignment of sunlight on high-altitude clouds beneath the satellites' orbits.
Who was Leonard Perroots and what role did he play in Able Archer 83?
Lieutenant General Leonard H. Perroots was the assistant chief of staff of the U.S. Air Force in Europe during Able Archer 83. He noticed unusual Soviet military activity during the exercise but advised against placing NATO forces on increased alert, instead recommending they wait to see if the Soviet behavior was caused by the exercise itself. A 1990 report by the President's Intelligence Advisory Board commended Perroots for that decision, and a later memorandum he wrote confirmed that a NATO countermove could have instigated a nuclear conflict.
How did Able Archer 83 affect President Reagan's views on nuclear war?
After receiving intelligence reports about the Soviet reaction to Able Archer 83, Reagan was deeply unsettled. He had already been shaken by a television film about nuclear destruction and a Pentagon war-game briefing in October 1983. Historian Beth A. Fischer argues in her book The Reagan Reversal that Able Archer 83 significantly contributed to Reagan's shift from confrontation to rapprochement with the Soviet Union, a change that led to his meetings with Mikhail Gorbachev in Geneva in 1985 and ultimately to the 1987 Intermediate-Range Nuclear Forces Treaty.
When were the Able Archer 83 documents declassified?
The President's Intelligence Advisory Board's 1990 report on the exercise was declassified in 2015 after a 12-year legal battle by the National Security Archive under the Freedom of Information Act. In February 2021, the U.S. State Department's Historian's Office released the Perroots memorandum as part of the Foreign Relations of the United States collection, confirming for the first time that Soviet commanders had loaded nuclear warheads onto bombers during the exercise.