Massive retaliation

Massive retaliation, also known as a massive response or massive deterrence, is a military doctrine and nuclear strategy in which a state commits itself to retaliate in much greater force in the event of an attack.

In the event of an attack from an aggressor, a state would massively retaliate by using a force disproportionate to the size of the attack.

The aim of massive retaliation is to deter another state from initially attacking. For such a strategy to work, it must be made public knowledge to all possible aggressors. The aggressor also must believe that the state announcing the policy has the ability to maintain second-strike capability in the event of an attack. It must also believe that the defending state is willing to go through with the deterrent threat, which would likely involve the use of nuclear weapons on a massive scale.

Massive retaliation works on the same principles as mutual assured destruction (MAD), with the important caveat that even a minor conventional attack on a nuclear state could conceivably result in all-out nuclear retaliation. However at the time when massive retaliation became policy, there was no MAD, because the Soviet Union lacked a second strike capability throughout the 1950s.

In August 1945, towards the end of the Pacific theater of World War II, the United States delivered nuclear attacks on Hiroshima and Nagasaki in Japan. Four years later, on August 9, 1949, the Soviet Union developed its own nuclear weapons. At the time, both sides lacked the means to effectively use nuclear devices against each other. Eventually with nuclear triads being established, both countries were quickly increasing their ability to deliver nuclear weapons into the interior of the opposing country.

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