8.2: The Cold War


AP Theme

Cultural Developments and Interactions

Learning Objective 8B

Explain the causes and effects of the ideological struggle of the Cold War.

Historical Development 1

The global balance of economic and political power shifted during and after World War II and rapidly evolved into the Cold War. The democracy of the United States and the authoritarian communist Soviet Union emerged as superpowers, which led to ideological conflict and a power struggle between capitalism and communism across the globe.

Historical Development 2

Groups and individuals, including the Non-Aligned Movement, opposed and promoted alternatives to the existing economic, political, and social orders.


The Causes and Effects of the Early Cold War (1945-1955)

The Cold War was a 50-year conflict that developed after World War II between the United States and its allies and the Soviet Union and its allies. The Americans supported capitalist economics, while the Soviets supported communist economics. The United States and the Soviet Union avoided direct military conflict for fear that the war would go nuclear. As a result, the adversaries fought through a series of proxy conflicts. They supported opposing groups in these conflicts by providing money and military support but did not directly fight each other.

COMPARISON: The American and Soviet Alliances   

The United States and Its Major Allies 

  • Britain
  • France
  • Italy
  • Western Germany
  • Japan
  • South Korea
  • Australia
  • Turkey

The Soviet Union and Its Major Allies

  • Eastern Germany
  • Poland
  • Cuba
  • Vietnam
  • China
  • Czechoslovakia
  • Hungary

Causes of the Cold War

There were multiple causes of the Cold War.

The Yalta Conference

Near the end of World War Two, the Yalta Conference took place in a Russian resort town in Crimea from February 4–11, 1945. At Yalta, U.S. President Franklin D. Roosevelt, British Prime Minister Winston Churchill, and Soviet Premier Joseph Stalin made important decisions regarding the future progress of the war and how they would rebuild the postwar world.

The Americans and the British agreed that future governments of the Eastern European nations bordering the Soviet Union should be “friendly” to the Soviet regime. At the same time, the Soviets pledged to allow free elections in all territories liberated from Nazi Germany. Negotiators also released a declaration on Poland, providing for the inclusion of Communists in the postwar national government.

The failure of Yalta: With the death of Franklin D. Roosevelt on April 12, 1945, Harry S. Truman became the thirty-third president of the United States. By the end of April, the new Truman administration clashed with the Soviets over their influence in Eastern Europe. The Soviets quickly disregarded their promise of free and fair elections in former NAZI territories liberated by the Soviets. The Soviets installed communist dictatorships in Poland and all other East European nations. Alarmed at the perceived lack of cooperation on the part of the Soviets, many Americans began to criticize Roosevelt’s handling of the Yalta negotiations.

New global superpowers

In the century before World War II, England and France were the world’s global superpowers. By the end of the war, their societies were destroyed and exhausted by war. America and the Soviet Union quickly rose as the world’s new industrial powerhouses.

Competing economic ideologies

The capitalist economy of the United States and the communist economy in the Soviet Union resulted in the world’s two superpowers having vastly different views on wealth distribution and the role of government in the economy.

The United States
The Soviet Union
Emphasis on individual rights
Focus on group and community rights
Governmet power
Wealth distirubtion
The goal is more equal distributions of wealth–but it has never worked
Factors of production (land, labor, and capital)
Privately owned
Owned by the state
More free and competitive
Less free and competitive
Sources of business capital (investment)
Primarily private, but some state investment
State investment

The iron curtain

The Iron Curtain was a symbolic political boundary that divided Europe into two separate areas after World War II until the end of the Cold War in 1991. Winston Churchill first used the term to describe Cold War Europe in his “Sinews of Peace” address on March 5, 1946, at Westminster College in Fulton, Missouri. On the east side of the Iron Curtain were the countries connected to or influenced by the Soviet Union, while on the west side were the countries that were NATO members or neutral nations. In many border regions between Soviet and non-Soviet Europe, the Iron Curtain took the physical form of barbed wire fences and border walls watched over by guard towers to prevent movement between communist and non-communist Europe. Soviet governments built most physical barriers to prevent their citizens from immigrating from communist areas.


After World War II, European powers lost control of their colonies across the Caribbean, Africa, and Asia. As European powers left colonies, America sought to prevent the expansion of communism into newly independent nations by supporting anti-communist groups throughout decolonized nations.

The Effects of the Cold War (1945-1955)

The start of the Cold War resulted in the international responses. 

The Truman Doctrine and Containment

The Truman Doctrine arose from a speech delivered by President Truman before a joint session of Congress on March 12, 1947.

What was the Truman Doctrine?

The Truman Doctrine established that the United States would provide political, military, and economic assistance to nations threatened militarily by the Soviet Union. Before the Truman Doctrine, the United States generally stayed out of conflicts in faraway conflicts that did not directly impact the United States. Now, the United States would directly confront communist expansion anywhere globally. The goal would be to “contain” communism and prevent its spread.

Why was the Truman Doctrine created?

The purpose of the Truman Doctrine was to provide military and economic aid to prevent the spread of communism, which the United States government feared would eventually threaten the American capitalist system.

The immediate cause for the speech and new American foreign policy was a recent announcement by the British government that it would no longer provide military and economic assistance to the Greek government in its civil war against the Greek Communist Party. Truman asked Congress to support the Greek government against the Communists. He also asked Congress to assist Turkey since that nation had previously been dependent on British aid.

The U.S. Government believed that the Soviet Union supported the Greek Communist war effort and worried that if the Communists prevailed in the Greek civil war, the Soviets would influence Greek policy. 

The Marshall Plan

The Marshall Plan was one of the most significant post-World War II events. The plan was named after United States Secretary of State George C. Marshall and President signed into law by President Truman on April 3, 1948. 

What was the Marshall Plan?

The Marshall plan was 13.3 billion dollars in economic assistance provided by the United States to Western European nations to restore the economy and infrastructure of Western Europe.

Why was the Marshall Plan created?

When World War II ended in 1945, Europe lay in ruins with its cities and economy shattered. Western leaders worried that Europeans might turn to communism in these conditions to relieve their suffering. Marshall plan funds sought to rebuild and reduce suffering from harsh post-war economic conditions.

For the United States, the Marshall Plan also provided markets for American goods, created dependable trading partners, and supported the development of stable democratic governments in Western Europe.

The Non-aligned movement

In Belgrade in 1961, Yugoslavia’s President, Josip Broz Tito, India’s first Prime Minister, Jawaharlal Nehru, Egypt’s second President, Gamal Abdel Nasser, Ghana’s first president Kwame Nkrumah, and Indonesia’s first President, Sukarno, came together and founded the Non-Aligned Movement.

What is the non-aligned movement?

The Non-Aligned Movement (NAM) is an international organization of countries that reject pressure to choose sides and join international power blocs.

Why were the goals of the non-aligned movement?

All five leaders believed that developing countries should not help the Western or Eastern blocs in the Cold War. They also thought that developing countries should not be capitalist or communist but should elements from both systems and use them in ways that benefited their people.

The Havana Declaration of 1979 said that the purpose of the non-aligned organization is to help countries keep their “national independence” in their “struggle against imperialism, colonialism… and all forms of oppression.”