Why did the ussr and the US avoid direct military action during the Cold War?

The USSR and the US avoided direct military action during the Cold War primarily due to the threat of nuclear annihilation, as both nations possessed vast arsenals of nuclear weapons capable of mutually assured destruction. Additionally, both superpowers engaged in proxy wars and political maneuvering to expand their influence without escalating to direct confrontation. Diplomatic efforts, such as treaties and summits, also played a role in preventing military conflict, as leaders sought to manage tensions and avoid catastrophic outcomes.