Dead Hand (nuclear war)

Dead Hand (Russian: Система «Периметр», Systema "Perimetr", lit. "Perimeter" System, with the GRAU Index 15E601, Cyrillic: 15Э601), also known as Perimeter, was a Cold-War-era automatic nuclear-control system used by the Soviet Union. General speculation from insiders alleges that the system remains in use in post-Soviet Russia. An example of fail-deadly and mutual assured destruction deterrence, it can automatically trigger the launch of the Russian intercontinental ballistic missiles (ICBMs) by sending a pre-entered highest-authority order from the General Staff of the Armed Forces, Strategic Missile Force Management to command posts and individual silos if a nuclear strike is detected by seismic, light, radioactivity, and overpressure sensors even with the commanding elements fully destroyed. By most accounts, it is normally switched off and is supposed to be activated during dangerous crises only; however, it is said to remain fully functional and able to serve its purpose whenever it may be needed. A similar system existed in the US known as the Emergency Rocket Communications System (ERCS).

"Perimetr" appeared as an alternative system for all units armed with nuclear weapons. It was meant to be a backup communication system, in case the key components of the "Kazbek" command system and the link to the Strategic Missile Forces are destroyed by a first-strike in accordance with the concept developed in the US called "Limited nuclear war".

In order to ensure its functionality the system was originally designed as fully automatic, and with the ability to decide on the adequate retaliatory strike on its own with no (or minimal) human involvement in the event of an all-out attack. Its existence is sometimes referred to as being "immoral", but is in fact the only deterring element that guarantees a fail-deadly retaliation when the adversary attempts to launch a pre-emptive strike.

According to Vladimir Yarynich, a developer of the system, this system also served as a buffer against hasty decisions based on unverified information by the country's leadership. Upon receiving warnings about a nuclear attack, the leader could activate the system, and then wait for further developments, assured by the fact that even the destruction of all key personnel with the authority to command the response to the attack could still not prevent a retaliatory strike. Thus, this eliminates the possibility of a false-alarm-triggered retaliation.

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Wikipedia