What incident brought the superpowers to the brink of open warfare?

In 1962 the Soviet Union began to secretly install missiles in Cuba to launch attacks on U. S. cities. The confrontation that followed, known as the Cuban missile crisis, brought the two superpowers to the brink of war before an agreement was reached to withdraw the missiles.

In 1962 the Soviet Union began to secretly install missiles in Cuba to launch attacks on U. S. cities.