World War I & the 1920s

You’ll be able to

Explain why the United States entered World War I and the war’s domestic effects
Analyze the tension between traditionalism and modernism in the 1920s
Describe the causes of the Great Depression

From neutrality to war

The U.S. entered World War I in 1917 after trying to stay neutral. German unrestricted submarine warfare (the sinking of the Lusitania and others) and the Zimmermann Telegram, in which Germany urged Mexico to attack the U.S., pushed Wilson to ask Congress for war "to make the world safe for democracy." At home, the war expanded federal power, mobilized the economy, and fueled repression — the Espionage and Sedition Acts punished dissent. Wilson’s idealistic Fourteen Points and League of Nations were then rejected by a Senate wary of foreign entanglement.

A decade of clashing values

The 1920s pitted modern, urban culture against traditional, rural values. Modernism brought jazz, the Harlem Renaissance, consumer culture, cars, and the "New Woman." Reaction was equally strong: Prohibition, a revived Ku Klux Klan, immigration quota laws (1924), and the Scopes Trial clash over teaching evolution. Nativism and the "Red Scare" targeted immigrants and radicals. This cultural civil war between cosmopolitan and traditional America defined the decade.

The road to the Depression

The prosperity of the 1920s rested on shaky foundations. Overproduction outran what consumers could buy, wealth was highly unequal, farmers and workers lagged, and reckless stock speculation on borrowed money inflated a bubble. When the stock market crashed in October 1929, it exposed these weaknesses; bank failures, collapsing demand, and the Dust Bowl deepened the spiral into the Great Depression, the worst economic crisis in the nation’s history, with unemployment reaching roughly 25 percent.

Worked example

Briefly explain ONE reason the United States abandoned neutrality and entered World War I in 1917.

1.Identify a specific provocation: Germany resumed unrestricted submarine warfare, sinking ships including those carrying Americans.
2.Add the diplomatic trigger: the Zimmermann Telegram revealed Germany urging Mexico to attack the United States.
3.Explain the effect: these actions inflamed American opinion and convinced Wilson that war was unavoidable.

Answer: Germany’s resumption of unrestricted submarine warfare, which threatened American lives and shipping, combined with the Zimmermann Telegram proposing a German-Mexican alliance against the U.S., turned American opinion toward war and led Wilson to seek a declaration in 1917.

Checkpoint

The Scopes Trial, Prohibition, and the revival of the Ku Klux Klan in the 1920s all reflect

Watch out

The stock market crash of 1929 did not by itself "cause" the Depression — it exposed deeper structural weaknesses: overproduction, extreme inequality, weak banks, and speculation. On the exam, treat the crash as a trigger, not the root cause.

Checkpoint

Which was an underlying structural cause of the Great Depression, rather than merely a trigger?

Answer the 2 checkpoints as you read.