The National Security Act of 1947 mandated a major reorganization of the foreign policy and military establishments of the U.S. Government.

In the immediate post-World War II period, Europe remained ravaged by war and thus susceptible to exploitation by an internal and external Communist threat. In a June 5, 1947, speech to the graduating class at Harvard University, Secretary of State George C. Marshall issued a call for a comprehensive program to rebuild Europe.

In the early years of the cold war Congressional, press, and public scrutiny of Department of State conduct of foreign policy turned into direct attacks not only on policies, but also on personnel.

In early 1961 President John F. Kennedy concluded that Fidel Castro was a Soviet client working to subvert Latin America.

1946-1968 U.S. Government meets the challenges of the Soviet bloc and contains communism. The Kennedy administration creates the Peace Corps and reinvigorates foreign aid.

George F. Kennan, a career Foreign Service Officer, formulated the policy of "containment," the basic United States strategy for fighting the cold war (1947-1989) with the Soviet Union. Kennan's ideas, which became the basis of the Truman administration's foreign policy, first came to public attention in 1947 in the form of an anonymous contribution to the journal Foreign Affairs, the so-called "X-Article."

As the cold war came to dominate U.S. foreign policy, America extended security commitments to two nations in Northeast Asia—the Republic of Korea and Japan.

At the end of World War II Berlin, former capital of the Third Reich, was a divided city in a divided country.

Growing out of the fear of increased Soviet and Cuban influence in Latin America, the 1961-1969 Alliance for Progress was in essence a Marshall Plan for Latin America.