What conflict existed between the US and the Soviet Union characterized by threats of nuclear war without direct military engagement?

The conflict characterized by threats of nuclear war without direct military engagement between the US and the Soviet Union is known as the Cold War. This geopolitical tension lasted approximately from the end of World War II until the early 1990s. During this period, the two superpowers engaged in an arms race, including the accumulation of nuclear weapons, and they fought for influence around the world through proxy wars and ideological competition, notably in Europe, Asia, and Latin America.

The Cold War is distinct in that, although it involved numerous crises, such as the Cuban Missile Crisis and the Berlin Wall's construction, it never escalated into direct military confrontation between the US and the Soviet Union. The overarching fear of mutual destruction from nuclear warfare acted as a deterrent to direct conflict.

The other conflicts listed, such as the Vietnam War, World War II, and the Gulf War, involved direct military engagement and a different set of geopolitical dynamics rather than the underlying ideological and strategic standoff characteristic of the Cold War.