AP U.S. History · Lesson 1

Containment abroad and at home

Know Know it

After 1945 the United States and the Soviet Union, wartime allies, became rivals in a Cold War: a long contest between two systems, waged with alliances, aid, an arms race and wars fought through other nations rather than direct battle between the two powers. American diplomat George Kennan argued for containment: holding Soviet influence inside the areas it already controlled until the Soviet system weakened from within.

Containment shaped a series of commitments. The Truman Doctrine (1947) promised aid to nations resisting communist pressure, beginning with Greece and Turkey. The Marshall Plan (1948) sent about 13 billion dollars to rebuild Western Europe's economies. When the Soviets blockaded West Berlin, an American and British airlift supplied the city for almost a year (1948 to 1949). In 1949 the United States joined its first peacetime military alliance, NATO.

In 1949 the Soviet Union tested an atomic bomb and Communists won China's civil war. A secret 1950 report, NSC-68, called for a huge military buildup, and the Korean War (1950 to 1953) soon tested containment: U.S.-led United Nations forces pushed back North Korea's invasion of the South, China entered the war, and an armistice left Korea divided near where the fighting began. Truman fired General Douglas MacArthur in 1951 for publicly challenging his policy of limited war.

Fear of communism reshaped life at home in a Second Red Scare. A federal loyalty program screened government workers, the House Un-American Activities Committee investigated Hollywood and other fields, and Julius and Ethel Rosenberg were executed in 1953 for conspiring to pass atomic secrets to the Soviets. Senator Joseph McCarthy's sweeping and often unsupported charges of communists in government gave the era a name, McCarthyism.

Under Eisenhower the arms race grew. The Soviet launch of Sputnik in 1957 alarmed Americans and led to new federal spending on science and space. The CIA helped overthrow governments in Iran (1953) and Guatemala (1954). Under Kennedy, the failed Bay of Pigs invasion of Cuba (1961) was followed by the Cuban Missile Crisis (1962), when Soviet missiles in Cuba brought the two powers close to nuclear war before the Soviets agreed to remove them.

Containment also drew the United States into Vietnam. After Vietnamese forces led by Ho Chi Minh defeated France in 1954, Vietnam was split into a communist North and a U.S.-backed South. Eisenhower warned that if one nation fell to communism its neighbors would follow, the domino theory. Kennedy sent thousands of military advisers. After reported attacks on U.S. destroyers in 1964, Congress passed the Gulf of Tonkin Resolution, and in 1965 Johnson began sustained bombing of the North and sent ground combat troops; by 1968 more than 500,000 Americans were serving in Vietnam.

Containment in action, 1947 to 1962
YearPolicy or eventTool used
1947Truman DoctrineEconomic and military aid to Greece and Turkey
1948Marshall PlanEconomic aid to rebuild Western Europe
1949NATOA military alliance for mutual defense
1950–1953Korean WarA limited war to restore a divided Korea
1962Cuban Missile CrisisA naval quarantine and negotiation

Trap Containment is not rollback

Containment meant stopping communism from spreading, not freeing places already under Soviet control. When Hungarians rose against Soviet rule in 1956, the United States did not send forces to help them. If a choice says Cold War presidents set out to overthrow communist rule in Eastern Europe by force, it misstates the policy.

Worked example Easy

What was the main goal of the Marshall Plan?

  1. To station U.S. troops permanently in every Western European capital
  2. To rebuild Western European economies and weaken communism’s appealAnswer
  3. To make Germany pay reparations for the costs of the war in Europe
  4. To divide the defeated Germany into four zones run by the Allies

How to solve it

  1. The Marshall Plan was a program of economic aid.
  2. Its aim was recovery in Western Europe, which leaders saw as a defense against communism.

Why each choice is right or wrong

  • A. Incorrect. The Marshall Plan was economic aid; American troops in Europe came through NATO and the occupation of Germany.
  • B. Correct. Marshall Plan aid of about 13 billion dollars helped Western Europe recover, on the view that prosperous nations would resist communism.
  • C. Incorrect. The plan sent aid into Western Europe, including western Germany, rather than collecting reparations from it.
  • D. Incorrect. The four occupation zones were agreed on in 1945, before the Marshall Plan, and were not its purpose.

Explain Explain it

Task verbs: explain, compare

To explain a Cold War decision, connect it to containment in one step: what spread of communist influence did leaders fear, and how was the action meant to stop it? To compare two Cold War events, name what the United States did in each and whether its goal was the same.

Worked example Medium

From John F. Kennedy, inaugural address, January 20, 1961 (public domain)

Let every nation know, whether it wishes us well or ill, that we shall pay any price, bear any burden, meet any hardship, support any friend, oppose any foe, in order to assure the survival and the success of liberty.

The commitment in this excerpt is most consistent with which earlier policy?

  1. The Neutrality Acts’ ban on selling arms to nations at war
  2. George Washington’s advice to steer clear of permanent alliances
  3. The Open Door notes’ call for equal trading rights in China
  4. The Truman Doctrine’s pledge to support free peoplesAnswer

How to solve it

  1. The excerpt promises to 'support any friend' and 'oppose any foe' to defend liberty.
  2. That global pledge grew out of containment, first stated as policy in the Truman Doctrine of 1947.

Why each choice is right or wrong

  • A. Incorrect. The Neutrality Acts of the 1930s tried to keep the nation out of foreign wars, the opposite of paying any price abroad.
  • B. Incorrect. Washington's 1796 advice warned against lasting foreign ties, while the excerpt pledges to support friends anywhere.
  • C. Incorrect. The Open Door notes sought trade access in one country; they made no pledge to defend liberty worldwide.
  • D. Correct. Truman's 1947 pledge to help nations resist communist pressure began the global commitment that Kennedy's words renew.

Explain Your turn

Explain how the policy of containment led the United States to fight in Vietnam. Give one specific idea and one specific action.

Write it, then compare. Nothing you type here is saved or graded.

Compare with a model answer

A full answer does this

  • Gives a specific idea that tied containment to Vietnam
  • Gives a specific U.S. action that deepened the commitment in Vietnam

Model answer

Containment meant stopping the spread of communism, and leaders applied it to Vietnam through the domino theory: if South Vietnam fell to the communist North, they argued, its neighbors in Southeast Asia would fall next. Acting on that belief, Congress passed the Gulf of Tonkin Resolution in 1964, and Johnson used it to send ground combat troops to Vietnam in 1965.

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