Britain's former Prime Minister thought an "Iron Curtain" had defended across Europe, partitioning the free West from the communist East.
Harry Truman was the president after FDR in 1945. He favored the containment, and there was a test that came in Grease and Turkey because the US was interested in the oil. He then announced the Truman Doctrine. This pledged to support "freedom-loving peoples" against communist threats. This helped the Americans to view the world with America as free and communists as tyrannical. The United States send $400 Million to Grease and Turkey, and this was set for the cold war races.
George Marshall announced the Marshall Plan at the Harvard Commencement Address in June of 1947. This was in response to the economic chaos in Europe, that was brought on by a harsh winder that strengthened support for communism in France and Italy. They used US aids to combat economic stability that provided fertile fields for communism.
This was basically a new deal for Europe and it worked. Western Europe was rebuilt so that by 1950, production levels in industry had eclipsed pre-war levels, and Europe was on its way to becoming a US society.
Japan was rebuilt as well. General Douglas MacArthur was the dictator forcing Japan to adopt a new constitution. This was so that the women could vote and that Japan would foreswear war making US Japan's defense force.
Germany was experiencing the Berlin Crisis. At the end of the war, Germany split into the east and the west. Even though the capital was completely east, that was divided as well. In 1948, Stalin cut off roads to West Berlin. America responded with an 11 month airlift of supplied, which led to Stalin lifting the blockade in 1948 and building the Berlin Wall.
The program that was officially called the Fair Deal would increase minimum wage, extend national health insurance, and increase public housing and social security. BUT the American Medical Association was against Truman's Plan. And there was a global crusade against communism.
Originally, the war was focused on Europe, but it moved to Asia real fast. Korea, who was occupied by Japan, was divided into a north and south. In 1950, North Korea invaded the South, with wishful thinking of converting the whole country to communism. Because of this, Truman convinced the United Nations Security Council to allow them to use force to stop the invasion. American troops did a huge amount of the fighting, but it was MacArthur's counter attack that led his army to occupy most of North Korea. MacArthur wanted to push through the North and invade china with weapons, but Truman denied that. He started to criticize Truman, so he removed him from command. There eventually was a statement that settled the war. There was never a formal peace treaty, though.
Information from Foner Text and given video.