The Cuban Missile Crisis

Cuban missile crisis occurred in October 1962 when the United States learned that the Soviet Union had secretly installed missiles in Cuba. The missiles could have been used to launch nuclear attacks on American cities. The crisis was one of the most serious incidents of the Cold War, a period of intense U.S.-Soviet rivalry that had begun after World War II. The Soviet Union had placed the missiles in Cuba earlier in 1962, after Cuban leaders became convinced that the United States was planning to attack Cuba. During the Cold War, Cuba was an ally of the Soviet Union. President John F. Kennedy of the United States learned of the missiles' presence on October 16 and demanded that the Soviet Union remove them.

On October 22, he ordered a naval blockade of Cuba to stop further shipment of arms.The Soviet Union offered to remove the missiles if the United States would promise not to invade Cuba.The agreement between Kennedy and Khrushchev was kept secret because many Americans opposed such a deal. Almost all Americans thus thought that Kennedy had forced the Soviet Union to remove the missiles simply by threatening war.

These things that happened at that time was considered "the hottest moment in the cold war" because this was the only time that the Cold War was very close to begin into a Nuclear War.
At the beginning of September 1962, U-2 spy planes discovered that the Soviet Union was building surface-to-air missile launch sites. There was also an increase in the number of Soviet ships arriving in Cuba which the United States government feared were carrying new supplies of weapons. President John F. Kennedy complained to the Soviet Union about these developments and warned them that the United States would not accept offensive weapons were considered to be defensive) in Cuba.