The United States was one of the main drivers of the creation of the "global community" during this time. The US was motivated to create this global community by its Cold War fears.
During the Cold War, the US wanted the West (as well as any other part of the world that it could get) to be united against communism. This helped lead it to push for much more international cooperation. The US helped to create the UN and the IMF and the World Bank and other such things. It helped to create NATO and other treaty organization. The whole point of these things was to tie the "free world" together more closely so as to create a solid anti-communist front.