Dead Hand

CORE DEFINITION

Dead Hand, also translated as Dead Hand system (English: Dead Hand), with Russian code name Perimeter system (Russian: Система «Периметр», Systema "Perimetr"), was a nuclear weapons control device of the Soviet Union during the Cold War. It included a computer system and sensors that detected seismic waves, light, radiation, pressure, and other data to determine whether the Soviet Union had been subjected to a nuclear attack. If an attack was determined, the system would launch special "broadcast missiles" that carried no nuclear warheads but were equipped with a special electronic device that would broadcast to all intercontinental ballistic missiles within the Soviet Union, causing them to launch automatically upon receiving the broadcast (conceptually similar to the U.S. AN/DRC-8 Emergency Rocket Communications System). Thus, the system could still function even if all ground command and communication systems were destroyed, embodying the design principles of fail-deadly and mutually assured destruction. The system was likely semi-automatic; because the computer could misjudge for any reason and trigger a nuclear war, it likely had a human-controlled switch that was only activated during nuclear crises.