The main trigger for the start of the Cold War was the ideological and geopolitical tensions between the United States and the Soviet Union following World War II. The differing beliefs in capitalism and democracy versus communism and authoritarianism drove a wedge between the two superpowers. Events such as the Berlin Blockade in 1948-1949, the proliferation of nuclear weapons, and differing visions for post-war Europe spurred the conflict. The competition for global influence and power manifested through military alliances, economic strategies, and proxy wars, solidifying the divide between East and West for decades.