Even though the US and the Soviet Union fought as allies during World War II, the alliance crumbled with the end of the war. During the Potsdam Conference, the US wanted to contain the spread of the Soviets and the communist influence in Western Europe.
During Kennedy’s presidential campaign the Cold War theme was strongly present. During his inaugural address, he addressed the contest between the free world and the communists. The Bay of Pigs plan was a disaster, the entire force was killed or captured and Kennedy took responsibility for it.
After that Kennedy and Nikita Khrushchev met in Austria, the meeting was not so peaceful because Khrushchev threatened to cut the access from the allies to Berlin, this led to the construction of the Berlin Wall.
In 1962 the Russians stated to supply nuclear missiles to Cuba, Kennedy responded by placing a naval blockade around Cuba, with this Khrushchev removed the missiles. At the end of Kennedy’s presidency, the Limited Nuclear Test Ban Treaty softened the tensions and Washington and Moscow established a direct line of communication known as the "hotline".
