HiSET · Social Studies · 6 min read
World Wars, the Depression, and Global Change
- Identify the causes, major turning points, and social effects of World War I and World War II.
- Analyze the economic conditions that caused the Great Depression and how New Deal policies transformed the federal government.
- Explain the origins of the Cold War and evaluate historical evidence using primary and secondary sources.
World War I and the Home Front
Long-standing pressures helped cause World War I, but the immediate trigger was the assassination of Archduke Franz Ferdinand in June 1914. Four major long-term factors set the stage for war across Europe: militarism, tangled alliance systems, imperialism, and nationalism. Alliances helped spread the war, but countries entered for different reasons, and treaties did not automatically bring every alliance member into combat. Across the Atlantic, the United States chose not to get involved right away. The United States initially remained officially neutral, although its trade and loans increasingly favored the Allies.
That neutral stance gradually became impossible to keep. Germany began using unrestricted submarine warfare, sinking ships carrying civilians and eroding American neutrality. Tensions rose further after Britain shared the intercepted Zimmermann Telegram with U.S. officials and its contents became public in 1917. In this message, Germany proposed a secret military alliance with Mexico against the United States. Faced with direct security threats and attacks on civilian ships, the United States entered the war.
The war also transformed American society at home. During World War I, African Americans began leaving the rural South in large numbers to move to Northern cities in search of industrial jobs, an era known as the Great Migration. President Woodrow Wilson outlined his Fourteen Points for a lasting peace in January 1918, before the fighting stopped in November. He proposed the Fourteen Points as a peace framework, which included creating the League of Nations to resolve international disputes peacefully. However, the United States Senate rejected the Treaty of Versailles and refused to join the League of Nations, wanting to protect American national sovereignty from foreign entanglements.
Common mistakes
- Thinking the 1929 stock market crash was the only cause of the Great Depression, rather than recognizing underlying weaknesses such as overproduction and financial instability, followed by bank failures and tariffs that worsened the downturn.
- Confusing the Marshall Plan with the Truman Doctrine. The Truman Doctrine was a broad pledge of financial and military support to resist communist subjugation, whereas the Marshall Plan specifically provided billions of dollars to rebuild war-torn Western Europe.
- Believing the United States joined World War II as soon as fighting began in Europe; it remained officially out of the war while increasingly aiding the Allies and entered after Japan attacked Pearl Harbor on December 7, 1941.
- Assuming the New Deal ended after Herbert Hoover created it; Herbert Hoover relied on voluntary cooperation and rugged individualism, while Franklin D. Roosevelt championed the New Deal.
Key points
- Militarism, alliance systems, imperialism, and nationalism helped set the stage for World War I; the assassination of Archduke Franz Ferdinand triggered the crisis that began the war, while German submarine warfare and the Zimmermann Telegram contributed to U.S. entry.
- The Great Migration drew African Americans to Northern industrial jobs during World War I, while the Senate later rejected the Treaty of Versailles and the League of Nations.
- The Great Depression was fueled by overproduction, bank failures, and high tariffs like the Hawley-Smoot Tariff, leaving homeless Americans in Hoovervilles and prompting Dust Bowl migrations.
- Franklin D. Roosevelt's New Deal used programs like the CCC, WPA, FDIC, SEC, and Social Security Act to provide relief, recovery, and reform, expanding federal government authority.
- World War II mobilization ended the Great Depression; major milestones included Pearl Harbor, D-Day, and island-hopping, while the Manhattan Project began under President Roosevelt and produced the atomic bombs used under President Truman.
- The Cold War pitted the capitalist United States against the communist Soviet Union through containment policies like the Truman Doctrine, the Marshall Plan, and the NATO alliance.
- Global change accelerated after World War II through the collapse of European empires, the Non-Aligned Movement, and domestic pressures from the Second Red Scare.
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