Britannica Sources used in this answer

How did nuclear weapons discourage direct war between the United States and the Soviet Union?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

20th-century international relations American naval scholar Alfred Thayer Mahan, undated photo.

During the 20th century, nuclear weapons discouraged direct war between the United States and the Soviet Union primarily through the principle of deterrence, which evolved into the doctrine of mutual assured destruction (MAD).12

This strategy was founded on the understanding that any nuclear attack by one superpower would trigger an overwhelming counterattack, resulting in the annihilation of both nations. To ensure this deterrent remained effective, both countries developed a nuclear triad—comprising manned bombers, land-based ballistic missiles, and nuclear submarines—to guarantee a second strike capability.1

The logic of MAD created a tenuous equilibrium where both sides recognized that a full-scale nuclear exchange would be ruinous, effectively precluding an initial attack. While the two superpowers engaged in brinkmanship—such as during the Cuban missile crisis—the catastrophic potential of these weapons forced leaders to prioritize diplomatic communication and arms-control agreements, such as the Strategic Arms Limitation Talks, to manage the risk of accidental or intentional escalation.123