Able Archer 83 took place between November 2 – 11 , 1983 . This was a North Atlantic Treaty Organization ( N.A.T.O. ) strategic arms exercise conducted by the United States government in order to simulate an escalating nuclear conflict . Staffs walked through the procedural drill which included asking permission from N.A.T.O political authorities to fire nuclear weapons . The codes were changed for Able Archer as there were new message formats and periods of radio silence . Able Archer 83 occurred just two months after the shootdown incident of Korean Air Lines Flight 007 . The United States was simulating the deployment and use of the Pershing II nuclear missile system that was being developed at the time . The Soviets suspected the United States of performing a surprise nuclear attack with the Pershing II system , despite the fact that the Pershing II missiles were not delivered to Europe until November 22 , eleven days after the conclusion of Able Archer 83 . The Soviets believed the United States had determined that a nuclear war was technically winnable . The reason behind this rationale by the Soviet Union was related to the fact that the United States had just recently upgraded its Minuteman III ICBM to the Minuteman IIIA . This ICBM was several times more accurate and had twice the yield of its predecessors , thus making Soviet hardened nuclear silos a viable target . That same year , the United States also introduced the Trident C-4 submarine-launched ballistic missile . All of these factors combined to make the Able Archer 83 test and incredibly stressful and dangerous time
Korean Air Lines Flight 007
Korean Air Lines Flight 007
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