Before the start of World War II, the United States had little on the international agenda. The country still had to deal with the aftershocks of the Great Depression. Franklin Delano Roosevelt’s image and talks on the radio were soothing for the population that had to go through a lot, but the fact remained that the newly established then federal programs were not achieving the most desired result. The country was still technically within the Depression. Before World War II, the United States experienced the peak of inactivity on the international arena due to numerous economical issues of internal nature. Even during the first two years of the war that concerned Europe only initially, the participation was incredibly passive. Land-lease for Great Britain and other kinds of help including humanitarian missions were the most that the United States had to offer then. One day in 1941 changed everything.On December 7, 1941 Japan carried out a major assault against the United States base Pearl Harbor, Hawaii. Numerous ships were sunken and there were severe casualties. The attack was not expected. The event signaled full entry of the United States into the state of open warfare against Axis powers. The event also effectively finished the Great Depression. Needs of the front gave the final push to economy of the country and finally gave the United States a chance to concentrate undivided attention on international matters.
Victory in the war ensured further interest of the United States in the international affairs. President Truman immediately established the next enemy – the Soviet Union and announced the Truman Doctrine, which stated that no small or insignificant state should be given to the mercy of the Soviet regime, because it may start an undesirable chain reaction of Communism spreading. Marshall Plan promised any small under-developed country under threat of the Soviet influence investments and different kinds of assistance to ensure that the spread of Communism is as mitigated as possible. For the first time since Theodore Roosevelt the United States became interested in the fate of small countries on the other side of the globe. For the first time since Woodrow Wilson the United States have become mediators of different matters such as the Holocaust, in the aftermath of which Israel’s establishment was allowed to happen. Moreover, the United States never lost track of the new arch enemy that became the successor of fascist Germany – the Soviet Union.
Korean and Vietnam wars were the consequences of Truman’s doctrine and Marshall’s Plan. The US wanted to ensure that at least a part of Korea and part of Vietnam remains under the influence of western democracies. The goal was reached in Korea albeit at the expense of many lives while Vietnam became a crushing defeat. Despite several failures, the United States is yet to lose interest in the international sphere. If earlier, the willingness to control the international sphere was induced by the super power nemesis – the USSR – after its dissolution the US is driven with the desire to collect information, the most valuable resource of the 21st century and to use it to the advantage. So far, the most serious test for the US was the Cuban Missile Crisis, which demanded lots of careful steps and patience so as not to react on Soviet provocations. The US came out stronger out of the conflict with NATO alliance as a useful too for coordination between the US and allies.
The US has not been into isolationism since Pearl Harbor. So far, involvement into international affairs has proven mostly fruitful and beneficial in the big picture. Whether such a state of things will stay unchanged – remains to be seen.