Able Archer 83 was a ten-day NATO command post exercise starting on November 2, 1983 that spanned Western Europe, centred on the Supreme Headquarters Allied Powers Europe (SHAPE) Headquarters situated at Casteau, north of the Belgian city of Mons. Able Archer exercises simulated a period of conflict escalation, culminating in a coordinated nuclear release. The 1983 exercise incorporated a new, unique format of coded communication, radio silences, participation by heads of government, and a simulated DEFCON 1 nuclear alert.

The realistic nature of the 1983 exercise, coupled 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 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. This relatively obscure incident is considered by many historians to be the closest the world has come to nuclear war since the Cuban Missile Crisis of 1962.

Point of Divergence

In real life, the threat of nuclear war was over when Able Archer 83 ended on November 11, 1983. But, what if the Soviets believed it was actually a secret operation. This would depend on:

  1. The US sending its Pershing II missiles to Europe before November 23

Background to Able Archer


The greatest catalyst to the Able Archer war scare occurred two years earlier. In a May 1981 closed-session meeting of senior KGB officers and Soviet leaders, Leonid Brezhnev and KGB chairman Yuri Andropov announced that the United States was preparing a secret nuclear attack on the USSR. To combat this threat, Andropov announced, the KGB and GRU would begin Operation RYAN (РЯН), which was a Russian acronym for "Nuclear Missile Attack". It was the largest, most comprehensive peacetime intelligence-gathering operation in Soviet history. In all probability, the goal of Operation RYAN was to discover the first intent of a nuclear attack and then prevent it.

Psychological Operations and Korean Air 007

Psychological operations by the United States began mid-February 1981 and continued intermittently until 1983. These included a series of clandestine naval operations that stealthily accessed waters near the Greenland-Iceland-United Kingdom gap, and the Barents, Norwegian, Black, and Baltic seas, demonstrating how close NATO ships could get to critical Soviet military bases. American bombers also flew directly towards Soviet airspace, peeling off at the last moment, occasionally several times per week. These penetrations were designed to test Soviet radar vulnerability as well as demonstrate US capabilities in a nuclear war.

On September 1, 1983, Korean Air Lines Flight 007 was shot down near the Sea of Japan. This helped brin Soviet-American relations to their lowest point.

Operation Able Archer

On November 2, 1983, as Soviet intelligence services were attempting to detect the early signs of a nuclear attack, NATO began to simulate one. The exercise, codenamed Able Archer, involved numerous NATO allies and simulated NATO's Command, Control, and Communications procedures during a nuclear war. Some Soviet leadership, because of the preceding world events and the exercise's particularly realistic nature, believed, in accordance with Soviet military doctrine, that the exercise may have been a cover for an actual attack.

Finally, during Able Archer 83 NATO forces simulated a move through all alert phases, from DEFCON 5 to DEFCON 1. While these phases were simulated, alarmist KGB agents mistakenly reported them as actual. According to Soviet intelligence, NATO doctrine stated, "Operational readiness No 1 is declared when there are obvious indications of preparation to begin military operations. It is considered that war is inevitable and may start at any moment.

The Soviet Union, believing its only chance of surviving a NATO strike was to preempt it, readied its nuclear arsenal. The CIA reported activity in the Baltic Military District, in Czechoslovakia, and it determined that nuclear capable aircraft in Poland and East Germany were placed "on high alert status with readying of nuclear strike forces". Upon learning that US nuclear activity mirrored its hypothesized first strike activity, the Moscow Centre sent its residencies a flash telegram on November 9, incorrectly reporting an alert on American bases and frantically asking for further information regarding an American first strike. The alert precisely coincided with the seven- to ten-day period estimated between NATO's preliminary decision and an actual strike. This was the peak of the war scare.

Countdown to war

On November 7, 1983 the US sent 80 Pershing II missiles to West Germany. KGB agents reported this activity to Moscow, believing they were to be launched in coming days.

On September 26, 1983 Soviet missile warning systems had detected a U.S. missile strike, but the officer on duty, Lieutenant Colonel Stanislav Petrov, thought this to be a glitch and did not take action. Likewise, on November 11, Soviet missile early warning systems reported missile launches from West German missile sites. Petrov, again in command, dismissed this as an attack, but when a multitude of missiles was detected, he promptly reported it to his superiors.

When Moscow got word, they quickly authorized the release of the Soviet arsenal.

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