During the 1960s, what was a primary reason for tensions between the U.S. and the U.S.S.R.?

The tensions between the United States and the Soviet Union during the 1960s were significantly heightened due to nuclear weapons development in Cuba, particularly evident during the Cuban Missile Crisis in 1962. This crisis was triggered when the U.S. discovered that the Soviets were installing nuclear missiles in Cuba, just 90 miles off the coast of Florida. This situation not only posed a direct threat to U.S. national security but raised fears of a nuclear war, bringing the superpowers to the brink of conflict. The U.S. responded with a naval blockade and demanded the removal of the missiles, which led to intense negotiations and a critical moment in Cold War history.

While other factors like the space race or technological competition fueled rivalry, the immediate and urgent threat of nuclear weapons positioned the Cuban Missile Crisis as the most significant catalyst for tensions during the 1960s. Trade disputes over resources, although relevant in other contexts, did not play a central role in the high-stakes confrontations characteristic of this period.