The "Dead Hand" (known in Russia as *Perimeter*) is a Soviet-era automated nuclear weapons control system designed to ensure a retaliatory strike in the event of a decapitating nuclear attack on the Soviet Union. The system was created during the Cold War and was intended to trigger a massive nuclear response even if the Soviet leadership was killed or incapacitated in a surprise strike.

In its operation, the Dead Hand system would rely on various sensors to detect signs of a nuclear attack—such as the detection of a nuclear explosion, a significant drop in atmospheric pressure, or communications from certain military sites. If such a trigger was detected and the leadership was confirmed as dead or unreachable, the system could automatically launch a retaliatory nuclear strike, effectively ensuring that the USSR would have a second-strike capability in the event of a first-strike attack by the West.

Though it is unclear how much of the Dead Hand system remains in operation today, it was a key part of the Soviet Union's strategy for nuclear deterrence during the Cold War. The system's existence was a closely guarded secret for many years, and it is still the subject of much speculation and concern in discussions of nuclear safety and arms control.

Here are some hashtags related to the "Dead Hand" or Perimeter system that you might use:

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#NuclearWarfare
#NuclearStrategy
#SurvivalAssurance
#MADDoctrine (Mutually Assured Destruction)