Dead Hand (Perimeter)

A Soviet nuclear command system, codenamed Perimeter, built to order a retaliatory missile launch if the country's leaders were killed in an attack. How automatic it ever was is disputed.

Wikipedia describes Perimeter, index 15E601, as an automatic or semi-automatic control system for nuclear weapons that the Soviet Union built during the Cold War. It can set off launches of Russia's intercontinental ballistic missiles by transmitting an order entered in advance by the General Staff. Wikipedia says Russia still operates it.

David E. Hoffman told NPR's Fresh Air in 2009 that the system was definitely built, under the codename Perimeter, as a semiautomatic way to strike back. He said it gave Soviet leaders a backup if an attack wiped them out, while still leaving the fate of the world with three duty officers in a deep underground bunker. The same year Nicholas Thompson wrote in Wired that Yarynich, who spent thirty years in the Soviet General Staff and the Strategic Rocket Forces, had helped build a real, working doomsday device.

The National Security Archive at George Washington University, in a 2009 briefing book of interviews with former Soviet officials, noted doubts over whether the automatic launch mechanism was ever fully operational. In that design, command missiles would launch on their own and pass launch orders to groups of ICBMs.

In 2025 BBC News reported that Medvedev, a former Russian president, raised the threat of the dead hand in a Telegram post. The BBC said some military analysts took this to mean the retaliatory control system. The BBC's headline says Trump moved nuclear submarines after the comments.