Unit 7: Period 7: 1890–1945

Timeline and turning points

Date	Development	Why it matters
1898	Spanish-American War and annexation of Hawaii	U.S. overseas power expands
1901–1917	Progressive reform grows	Reformers use government to address industrial society’s problems
1917–1918	U.S. participation in World War I	Mobilization expands federal power at home and abroad
1920	Nineteenth Amendment	Voting discrimination on the basis of sex is prohibited
1929	Stock market crash	A financial crisis helps deepen the Great Depression
1933	Roosevelt takes office	The New Deal begins
1941	Pearl Harbor	The United States enters World War II
1944–1945	D-Day; Allied victory	Total war ends with the United States a global superpower

Imperialism and America’s role abroad

Industrial growth encouraged interest in foreign markets, investment, naval bases, and strategic routes. Alfred Thayer Mahan argued that sea power was essential to national strength. Imperialists also used racial and religious claims to justify ruling other peoples.

The Spanish-American War of 1898 grew from Cuba’s struggle against Spanish rule, U.S. economic interests, sensational reporting, and the explosion of the battleship Maine. The cause of the explosion was uncertain, but public pressure for war increased.

Spain’s defeat brought Puerto Rico, Guam, and the Philippines under U.S. control. Cuba became formally independent, but the Platt Amendment gave the United States extensive intervention rights and access to a naval base at Guantánamo Bay. The United States also annexed Hawaii in 1898, following the overthrow of Queen Liliʻuokalani by interests backed by U.S. involvement in 1893.

Filipino nationalists who had fought Spain resisted U.S. rule in the Philippine-American War. Anti-imperialists argued that colonial rule contradicted government by consent. Other opponents feared economic competition or racial incorporation, so opposition to empire did not always rest on equal-rights principles.

The imperial debate at home

Supporters of expansion argued that industrial production needed overseas outlets and that a modern navy required bases and coaling stations. Some missionaries and political leaders treated spreading Christianity or American institutions as an obligation. These claims presented national advantage and moral purpose as compatible, even when the people being governed opposed U.S. control.

The Anti-Imperialist League challenged annexation of the Philippines by invoking consent of the governed. Its coalition included people with very different views about race, business, and government. A businessman might fear the expense of empire, a labor leader might fear competition, and a reformer might object to denying self-government. Agreement against annexation did not imply agreement about equality.

The Teller Amendment had disclaimed an intention to annex Cuba during the war with Spain. The later Platt Amendment created substantial U.S. influence without formal annexation. Comparing the two shows how a commitment to independence could coexist with arrangements that limited another country’s practical sovereignty.

The Philippine-American War exposed the violence required to maintain an empire against resistance. Filipino nationalists had their own independence movement, so the conflict was not merely a transfer of administration from one colonial power to another. U.S. rule required defeating people who expected the end of Spanish rule to mean freedom.

Different approaches to intervention

Policy	Main approach
Open Door policy	Seek equal commercial access to China and oppose its division into exclusive foreign spheres
Roosevelt Corollary	Claim a U.S. role in intervening in Latin American countries to prevent European intervention
Dollar Diplomacy	Use investment and financial influence to advance U.S. interests
Wilson’s diplomacy	Emphasize moral principles while still using military intervention, including in Mexico and the Caribbean

The Panama Canal strengthened naval and commercial connections between the Atlantic and Pacific. Its construction followed U.S. support for Panama’s separation from Colombia and an agreement giving the United States control of the canal zone.

Progressivism

Progressives sought to address corruption, unsafe work, urban poverty, corporate abuses, and other problems associated with industrialization. They were not a single movement. Some emphasized democracy, others expert administration, moral reform, or social control.

Reform from local to national government

Muckrakers exposed abuses through investigative journalism. Upton Sinclair’s The Jungle helped build support for meat inspection and food regulation. Settlement-house workers connected direct services with demands for housing, labor, and public-health reform.

Reform	Purpose
Initiative, referendum, and recall	Give voters more direct influence over legislation and officeholders
Direct primaries	Reduce party leaders’ control over nominations
Sixteenth Amendment	Permit a federal income tax without apportionment among states
Seventeenth Amendment	Establish direct election of U.S. senators
Eighteenth Amendment	Prohibit the manufacture, sale, and transportation of intoxicating liquor
Nineteenth Amendment	Prohibit denial of voting rights on the basis of sex

Theodore Roosevelt’s Square Deal supported regulation, consumer protection, and conservation. He distinguished between corporations he considered useful and those abusing their power. William Howard Taft pursued antitrust enforcement but split with Roosevelt over policy and party leadership. In 1912, their division helped Woodrow Wilson win the presidency.

Wilson’s reforms included the Federal Reserve Act, Federal Trade Commission, and Clayton Antitrust Act. Conservation policies sought managed use of resources, while preservationists such as John Muir wanted stronger protection from development.

Progressive reformers often believed that trained professionals could solve problems that corrupt or uncoordinated local politics had failed to address. City commissions, public-health departments, building codes, and professional management reflected this confidence in expertise. Such reforms could improve services while shifting decisions away from ordinary voters.

The Triangle Shirtwaist fire of 1911 made unsafe working conditions difficult to dismiss as isolated accidents. The deaths of garment workers encouraged demands for workplace inspection, fire safety, and employer responsibility. Organizers and investigators converted public outrage into institutional reform; the disaster alone did not automatically change the law.

Suffrage campaigns also used different methods. Carrie Chapman Catt pursued organized lobbying and coordinated state and national campaigns, while Alice Paul used more confrontational tactics, including demonstrations directed at the federal government. Their approaches differed, but both helped increase the political cost of continued exclusion.

Conservation exposed disagreements within reform. Gifford Pinchot favored scientifically managed resource use, while preservationists wanted some landscapes protected from development. Both challenged unrestricted exploitation, but they disagreed over whether a dam or commercial use could represent responsible public management.

The limits of reform

Many Progressives ignored racial inequality or supported segregation and coercive policies. Wilson’s administration segregated federal workplaces. W. E. B. Du Bois and the NAACP pressed for civil rights, while other activists challenged lynching and discrimination outside mainstream white reform organizations.

Women’s suffrage expanded formal citizenship, but discriminatory state practices continued to block many Black women and other women of color from voting.

World War I

From neutrality to intervention

The United States initially remained neutral when war began in Europe in 1914. Trade and loans increasingly connected it to the Allies. German submarine warfare threatened shipping and American lives, including in the sinking of the Lusitania in 1915.

Germany’s resumption of unrestricted submarine warfare and the Zimmermann Telegram, proposing a German-Mexican alliance against the United States, helped push Wilson toward war in 1917. Wilson presented intervention as a defense of democracy and a chance to shape the peace.

Mobilization and civil liberties

The federal government used the draft, coordinated production through agencies such as the War Industries Board, promoted food conservation, and sold war bonds. The Committee on Public Information mobilized support through propaganda.

The Espionage Act and Sedition Act restricted dissent. Socialists, labor activists, and critics of the war faced prosecution. In Schenck v. United States, the Supreme Court upheld a wartime conviction, illustrating the narrow protection given to some speech during the conflict.

Labor demand accelerated the Great Migration of Black southerners to northern and midwestern cities. Migrants sought jobs and escape from Jim Crow, but they encountered housing discrimination and racial violence. Women also entered additional jobs during mobilization.

Migration, labor, and wartime expectations

Wartime industry needed workers at a moment when European immigration was disrupted. Black newspapers and community networks spread information about northern opportunities, encouraging migration out of the South. Leaving could mean escaping direct threats and gaining political influence through voting in places where disfranchisement was less entrenched.

Northern employers did not necessarily offer equality. Migrants often entered difficult jobs and segregated housing markets, while white workers sometimes treated them as competitors or strikebreakers. Tensions could lead to violence, as in East St. Louis in 1917 and the broader attacks of 1919. Economic opportunity and racial exclusion developed together.

The government sometimes encouraged cooperation between labor and management to avoid production stoppages. Wartime bargaining gains could prove fragile after peace, when employers sought to recover control and officials associated militancy with radicalism. The transition from mobilization to demobilization helps explain the wave of strikes and repression after 1918.

Wilson’s language of self-determination also raised expectations outside Europe. Colonized peoples could ask why a principle used to reorganize European territory should not apply to them. The peace settlement’s limits exposed a gap between universal rhetoric and the interests of victorious empires.

The peace settlement

Wilson’s Fourteen Points proposed open diplomacy, freer trade, self-determination, and a League of Nations. The Treaty of Versailles reflected compromises with Allied leaders who sought security, territory, and reparations.

The Senate rejected U.S. membership in the League. Some senators opposed it outright; others, including Henry Cabot Lodge, wanted reservations protecting congressional authority over war. Wilson’s refusal to accept major compromises helped defeat ratification.

The First Red Scare after the war combined fear of Bolshevism, labor unrest, and anarchist violence. The Palmer Raids targeted suspected radicals, often violating civil liberties. The racial violence of the Red Summer of 1919 exposed the limits of wartime promises of democracy.

The 1920s: prosperity and cultural conflict

Mass production, especially the automobile assembly line, lowered costs and supported consumer industries. Advertising and installment credit encouraged purchases of cars, radios, and household appliances. Republican administrations generally favored business, lower taxes, and limited regulation.

Prosperity was uneven. Farmers faced low prices and debt, many workers had limited purchasing power, and racial discrimination restricted opportunity. Rapid stock speculation did not mean the economy was equally healthy for everyone.

The Harlem Renaissance celebrated Black art, literature, and intellectual life. Langston Hughes, Zora Neale Hurston, and other figures explored Black experience and identity. Marcus Garvey promoted Black pride, economic independence, and Pan-African identification.

The image of the flapper symbolized changing gender expectations, but most women did not experience complete social or economic freedom. Movies, radio, and sports produced a more national mass culture.

Conflict	What was at stake
Scopes trial, 1925	Evolution, public education, and religious authority
Prohibition	Moral reform, individual behavior, enforcement, and organized crime
Revived Ku Klux Klan	White Protestant supremacy directed against Black Americans, immigrants, Catholics, and Jews
Immigration quotas, 1921 and 1924	Restriction of immigration, especially from southern and eastern Europe, alongside severe Asian exclusion

Consumer prosperity and underlying weakness

The automobile connected several sectors of the economy. Car production increased demand for steel, rubber, glass, oil, roads, and service businesses. It also changed settlement and leisure by making longer-distance travel more accessible. A single mass-produced product could therefore reorganize employment and daily routines far beyond its assembly line.

Installment credit let families buy goods before they had saved the full price. This expanded immediate demand but created obligations that became harder to meet if income fell. The same mechanism that supported consumption during growth could worsen distress during a downturn.

Agriculture did not share evenly in urban prosperity. Wartime demand had encouraged expansion, but postwar prices fell while farmers still owed debts incurred for land and machinery. The contrast helps explain why 1929 did not feel like the beginning of hardship for everyone; many rural communities had faced a prolonged crisis already.

The renewed Ku Klux Klan’s influence extended beyond the South. It defended a vision of white Protestant national identity and mobilized against Catholics, Jews, immigrants, and Black Americans. Its growth demonstrates that racial and religious exclusion were national political forces, not merely remnants of southern Reconstruction conflict.

The Great Depression

The stock market crash of 1929 was a major shock, but the Depression had multiple causes. Unequal income distribution limited purchasing power; farmers and businesses faced overproduction; banks were vulnerable to failures; debt and speculation increased risk; and international financial problems spread the crisis.

Bank failures destroyed savings and restricted credit. Falling demand led firms to cut production and jobs, which reduced demand further. The Smoot-Hawley Tariff and retaliatory tariffs worsened the contraction of international trade.

President Herbert Hoover initially emphasized voluntary cooperation and local relief. He later supported measures such as the Reconstruction Finance Corporation, but his response remained too limited for the scale of unemployment and hardship. The removal of the Bonus Army from Washington in 1932 further damaged his reputation.

During the Depression, deportation drives and coerced departures sent many people of Mexican ancestry to Mexico, including U.S. citizens. These Mexican repatriation campaigns reflected efforts to reserve jobs and relief for people officials considered more deserving, with racial identity often taking precedence over citizenship.

The Dust Bowl combined drought with farming practices that left soil vulnerable to erosion. Displaced families moved in search of work, often facing hostility in destination states.

The New Deal

Franklin D. Roosevelt expanded federal action through programs often grouped as relief, recovery, and reform. These goals overlapped: one program could provide immediate jobs while also building long-term infrastructure.

Program or law	Main function
FDIC	Insures bank deposits to reduce the risk of bank runs
CCC and WPA	Provide jobs through conservation and public projects
AAA	Seeks to raise agricultural prices by limiting production
TVA	Builds regional infrastructure and expands electricity access
Social Security Act	Establishes old-age benefits and other forms of social insurance and assistance
Wagner Act	Protects collective bargaining and establishes the National Labor Relations Board
SEC	Regulates securities markets
Fair Labor Standards Act	Establishes federal wage and hour standards and restricts child labor

Banking confidence and emergency action

A bank run occurred when depositors rushed to withdraw money because they feared a bank might fail. Banks did not keep every deposit in cash, since funds were lent or invested. Even an institution with valuable assets could collapse if it could not turn those assets into cash quickly enough to meet withdrawals.

Roosevelt’s bank holiday, emergency legislation, and public explanation of policy sought to interrupt this cycle of panic. Deposit insurance later reduced the incentive for small depositors to rush to withdraw at the first sign of trouble. Banking reform therefore addressed confidence and institutional design, not simply the quantity of government spending.

The New Deal developed experimentally. Early measures tried to stabilize prices and coordinate recovery; later measures placed greater emphasis on labor rights, employment, and social insurance. Treating it as a single plan fully designed in 1933 obscures how political pressure and disappointing results changed policy.

Labor organization and political change

The Congress of Industrial Organizations, initially developing within the labor movement before becoming a separate federation, organized workers across entire mass-production industries. Unlike an approach centered on separate skilled crafts, industrial unionism sought to bargain for large groups working within the same industry. Sit-down strikes and other tactics increased workers’ leverage while provoking intense opposition.

The Wagner Act strengthened legal protection for organizing, but workers still had to build unions and win recognition. Government action created an opening; it did not automatically supply workplace power. Growing union membership then helped build support for Democrats and sustained demands for economic security.

The recession of 1937–1938 showed that recovery remained fragile. Reduced federal support and tighter financial conditions contributed to renewed contraction. The episode strengthened arguments for continued public spending while providing critics with evidence that the New Deal had not established a self-sustaining recovery.

Opposition and limitations

Conservatives argued that the New Deal expanded federal power too far. Critics such as Huey Long argued that it did too little to redistribute wealth. The Supreme Court struck down some early programs, and Roosevelt’s proposed court expansion plan damaged his political standing.

The New Deal did not end racial or gender inequality. Agricultural and domestic workers were initially excluded from major protections, disproportionately affecting Black workers and women. Agricultural policy could displace tenant farmers, and local administration often reinforced discrimination.

The New Deal coalition brought together many urban workers, immigrants, white southerners, and an increasing share of Black voters. The federal government assumed greater responsibility for economic security, but capitalism and private ownership remained central.

World War II

From neutrality to global war

During the 1930s, Neutrality Acts reflected fears of repeating the path into World War I. As Axis aggression expanded, Roosevelt moved toward aid to the Allies through measures such as Lend-Lease.

Japan’s attack on Pearl Harbor on December 7, 1941, brought the United States into the war. Germany and Italy then declared war on the United States. The Allies pursued a Europe-first strategy while fighting Japan in the Pacific.

Midway checked Japanese expansion and shifted the naval balance in the Pacific.
D-Day opened a major western front in France in June 1944.
Island hopping captured strategically important Pacific positions while bypassing others.
The Soviet Union bore enormous losses fighting Germany on the eastern front; Allied victory depended on a coalition, not U.S. action alone.

Why neutrality became harder to maintain

Memories of World War I led many Americans to suspect that trade, loans, and arms sales could drag the country into another conflict. Neutrality legislation tried to prevent that sequence by restricting transactions with belligerents. But treating aggressors and their opponents identically could leave threatened countries without supplies while expansionist powers continued attacking.

Roosevelt gradually argued that aiding countries fighting the Axis would strengthen U.S. security. Cash-and-carry arrangements and later Lend-Lease moved policy toward support without initially deploying an American combat army into the European war. Neutrality became a debate about which actions actually reduced the danger of eventual war.

In the Pacific, Japanese expansion in China and Southeast Asia collided with U.S. strategic and commercial interests. American economic restrictions, including oil restrictions, increased pressure on Japan. Japanese leaders chose a wider war rather than retreat from imperial ambitions. Pearl Harbor was therefore connected to a broader struggle over expansion and resources, not an isolated event without prior conflict.

Logistics and coalition warfare

The United States supplied ships, aircraft, vehicles, food, and other materials on an enormous scale. Keeping supply routes open was essential: producing equipment did little good if it could not reach the people using it. The struggle in the Atlantic and the capture of strategic Pacific positions were therefore logistical as well as battlefield contests.

Allied leaders disagreed over strategy and the timing of a western front. The Soviet Union wanted relief from the pressure of fighting Germany, while Britain and the United States weighed military readiness and competing theaters. Cooperation was necessary for victory without requiring complete agreement about the postwar world.

Mobilization and inequality at home

Federal spending, industrial conversion, rationing, and mass military service reorganized the economy. Women entered industrial work in greater numbers, though many were pushed out of those jobs after the war. The Bracero Program recruited Mexican workers under temporary labor agreements.

The Double V campaign called for victory over fascism abroad and racism at home. After A. Philip Randolph threatened a march on Washington, Roosevelt prohibited discrimination in defense employment and created the Fair Employment Practice Committee. Enforcement remained uneven, and the armed forces remained segregated during the war.

Executive Order 9066 enabled the forced removal and incarceration of people of Japanese ancestry, most of them U.S. citizens. In Korematsu v. United States, the Supreme Court upheld the challenged exclusion order. There was no individualized proof that the people removed posed a security threat.

Victory and the postwar order

Germany surrendered in May 1945. In August, the United States dropped atomic bombs on Hiroshima and Nagasaki, and the Soviet Union entered the war against Japan. Japan surrendered soon afterward. The relative importance of these pressures and the alternatives available to U.S. leaders remain subjects of historical debate.

The Holocaust and other wartime atrocities exposed the consequences of Nazi racial ideology and mass murder. U.S. immigration restrictions had limited refuge for many people fleeing persecution.

The war left the United States with enormous industrial and military power. The United Nations and new international financial institutions reflected efforts to prevent another global collapse, while tensions with the Soviet Union laid the groundwork for the Cold War.

War, the economy, and the international order

Wartime mobilization used federal spending and coordination on a scale far beyond the New Deal. Production demands absorbed unemployment, while rationing and price controls attempted to manage shortages and inflation. Families postponed purchases, accumulated savings, and prepared for a postwar economy that would redirect factories toward civilian consumption.

The GI Bill of 1944 anticipated veterans’ return by supporting education, training, and housing. Its later effects belong largely to the postwar period, but its passage reflected wartime planning to avoid the instability that had followed World War I. Unequal access to the benefits would also shape postwar inequality.

The Bretton Woods agreements helped establish institutions intended to stabilize international finance and support reconstruction. The United Nations created a forum for diplomacy and collective security while giving the major powers special authority through the Security Council. These arrangements reflected both ideals of cooperation and the distribution of power at the war’s end.

Comparing 1919 with 1945 reveals a major shift. After World War I, the United States refused membership in the League of Nations. After World War II, it accepted a central role in new international institutions and maintained much larger global commitments. The difference came from wartime experience, economic power, and the emerging rivalry with the Soviet Union rather than from a disappearance of domestic disagreement.

Connections and recap

Historical connection	Evidence from this period
Expanding federal responsibility	Progressive regulation, wartime mobilization, and the New Deal
Democracy and exclusion	Colonial rule, speech restrictions, immigration quotas, and incarceration
Migration and social change	Great Migration, urban culture, and wartime employment
Global power	Overseas empire, world wars, and international institutions