The Cold war started for many reasons. In 1945 after World War II (WWII) the alliance between the United States, United Kingdom and USSR ended. A rivalry between Communism and Capitalism began which lead to the Cold War. At the end of WWII Germany was divided into four zones controlled by the UK, France, US, and USSR. The lack of mutual agreement in the division of Germany was another mark that started the cold war. Another spark was when the US dropped the atomic bomb on Japan, USSR was mad that US had developed this technology secretly. Then Truman and Churchill were angry with Stalin when he signed a border treaty with Poland.
             By nineteen forty eight USSR controlled Poland, East Germany, Hungry, Romania, Bulgaria, and Czechoslovakia. Every one believed the Stalin made an iron Curtin dividing USSR from the rest of Europe. The US and UK were also agree at Stalin for the fact he promised free election at Yalta and did not hold them. The Cold war was a result of clashes between Communism and Capitalism. There were two opposing world views.
             Another cause of the build up to the Cold War was the intransigent attitude of both sides. The Soviet Union was extremely concerned about its security after having been invaded twice in the twentieth century. In 1945 America created and used the atomic bomb against Japan and the USSR was determined to create one of its own. Both the USSR and the USA built up huge arsenals of Inter-Continental Ballistic Missiles (ICBMs). The United States tested a hydrogen bomb in 1952 and in November 1955, the USSR developed one too. After that the USA moved its bombers into Europe. In 1955 West Germany was allowed to re-arm and join NATO. Russia responded by forming the Warsaw Mutual Defense Pact with its buffer zone neighbors. In 1957 the Soviets used a missile to launch Sputnik 1 into orbit around the earth.
             The arms race evolved into a space race as the United States rushed to launch its o...