The United Nations came into existence on October 24, 1945, after 29 nations had ratified the Charter.
Marshall Plan
Iron Curtain speech, speech delivered by former British prime minister Winston Churchill in Fulton, Missouri, on March 5, 1946, in which he stressed the necessity for the United States and Britain to act as the guardians of peace and stability against the menace of Soviet communism, which had lowered an “iron curtain
NATO
With the Truman Doctrine, President Harry S. Truman established that the United States would provide political, military and economic assistance to all democratic nations under threat from external or internal authoritarian forces.
Warsaw Pact
On April 3, 1948, President Truman signed the Economic Recovery Act of 1948. It became known as the Marshall Plan, named for Secretary of State George Marshall, who in 1947 proposed that the United States provide economic assistance to restore the economic infrastructure of postwar Europe.
The North Atlantic Treaty Organization was created in 1949 by the United States, Canada, and several Western European nations to provide collective security against the Soviet Union. NATO was the first peacetime military alliance the United States entered into outside of the Western Hemisphere.
Formally known as the Treaty of Friendship, Co-operation and Mutual Assistance, the Warsaw Pact was created on 14 May 1955, immediately after the accession of West Germany to the Alliance.