Unit X

Key Terms

Truman Doctrine


Pledged the United States to the containment of communism in Europe and elsewhere. The doctrine was the foundation of Truman's foreign policy. It impelled the United States to support any nation whose stability was threatened by communism or the Soviet Union.

Marshall Plan


U.S. program to aid war-torn Europe, also known as the European Recovery Program. Also a cornerstone in the U.S. use of economic policy to contain communism.



"House Un-American Activities Committee."
Originally intended to ferret out pro-Fascists, it later investigated "un-American propaganda" that attacked constitutional government.

Get communists out of Hollywood!



National Security Council (NSC) Paper calling for an expanded and aggressive U.S. defense policy, including greater military spending and higher taxes. Committed US to a military approach to the Cold War.

38th Parallel


Other Important Terms

E.O. 9835


Signed by Harry Truman in 1947 to establish a loyalty program requiring federal employees to sign loyalty oaths and undergo security checks.



"National Security Council."
The formal policy-making body for national defense and foreign relations, created in 1947 and consisting of the president, the secretary of defense, the secretary of state, and others appointed by the president.

Federal Employees Loyalty and Security Program


Established by E.O. 9835. Barred Communists and fascists from federal employment and outlined procedures for investigating current and prospective federal employees.

Berlin blockade

1948 - 1949

Three-hundred-day Soviet blockade of land access to United States, British, and French occupation zones in Berlin.



Anti-Communist attitudes and actions associated with Senator Joe McCarthy in the early 1950s, including smear tactics and innuendo.

Immigration and Nationality Act


Also known as "McCarran Walter Immigration Act."
Reaffirmed the national origins quota system but tightened immigration controls, barring homosexuals and people considered subversive from entering the United States.