During the Cold War, the United States engaged in many aggressive policies both in America and abroad, in pursuance to fight communism and the spread of communist ideologies.Faced with a new challenge and global responsibilities the U.S. needed to preserve what it had fought for in World War II. It needed to contain the communist ideas flowing from the Soviet Union while preventing communist influence in America, without provoking World War III.The United States successfully utilized containment by the application of 3 methods, the Berlin airlift ,the Truman Doctrine, and the use of naval blockade. The Berlin airlift was one successful containment method in which the untied states responded to the soviet blockade of Berlin, successfully bringing food and medical supplies to allied controlled areas of Berlin.In June 1948, the Soviets blockaded all exterior access to Berlin from the west. This reprisal move was intended to send a sign to the U.S. and its Allies that the Soviet Union did not tolerate western interference in its territories. In response, President Truman made a decision that would allow the U.S. to deliver supplies to the Berlin people without fighting the Soviets. His proposal called for American aircrafts to airlift supplies to West Berlin. This plan was immediately accepted, and the Berlin Airlift began flying thousands of food and supplies to Berlin daily. In May of 1949, the Soviets lifted the blockade and allowed the free flow of supplies into West Berlin. Doing so caused the Soviet Union to lose in what was essentially a public relations war. This dispute proves that the Berlin Airlift was a successful containment method. The Truman Doctrine was another successful method of containment in which President Truman declared the US should give military support to countries threatened by Soviet forces or communist insurgency. In August of 1945 the Soviet Union invaded Korea, which had been under Japan’s control since 1910. Fearing that the Soviet Union would seize the entire peninsula, the United States quickly moved its own soldiers into South Korea. Japanese arms forces surrendered to the Soviets in the north and to the Americans in the south. In an effort to avoid a long-term controversy regarding Korea’s future, the United States and the Soviet Union agreed to divide Korea along the 38th parallel. In 1950, the Korea Peninsula was divided between an American-based government in the south and a Soviet-based government in the north. When North Korean soldiers invaded South Korea, the Truman administration took advantage of the opportunity to defend a noncommunist government from invasion by communist armed forces. Determined not to allow another country to be defeated by communism, and interested in supporting its anticommunist credentials, the Truman administration decided to provide military support for South Korea. The war continues for several years and finally ends in 1953, very close to the original boarders.The Truman Doctrine was a successful method of containment in which because the Truman administration decided to defend South Korea and its democratic ways, it effectively contained another nation from the communistic ideologies of the Soviet Union. The application of naval blockade preformed by the U.S. was yet another successful method of containment. In January 1959 Cuba becomes a communist country under the reign of Fidel Castro. as of may 1962 the Soviet Union secretly started to move thousands of soldiers, missiles and nuclear war heads to Cuba in intent to bomb America. Kennedy took recognition of the Soviets secret plan and chose to perform a naval blockade to ban the Soviets from bringing in any further military supplies to Cuba. After further negotiation, Khrushchev and Kennedy agreed on the withdraw of the weapons, and therefore improved relations and moved on, creating peace and avoiding further use of nuclear warfare. The use of naval blockade supported the US policy of containment by keeping the communist Soviet Union from bombing the US. In conclusion it is indisputable that the policy of containment was one of the most important factors in the Cold War. From the declaration of the Truman Doctrine, to America’s support in the Korean war, containment was the driving force behind all of these critical events and decisions. United States successfully utilized containment by the application of 3 methods, the Berlin Airlift ,the Truman Doctrine, and the use of naval blockade.