AP U.S. History Unit 7
Period 7: 1890–1945
~21 Class Periods | 10–17% AP Exam Weighting
📚 Essential Resources: Master this unit with our Period 7 flashcards, test yourself with the interactive quiz, and calculate your exam score with our AP score calculator.
7.1 Contextualizing Period 7
Overview
Period 7 (1890–1945) witnessed America's emergence as a global power through imperialism, two world wars, and significant domestic transformations. The era began with Progressive reforms addressing Gilded Age problems, expanded U.S. influence overseas, endured World War I, experienced the cultural conflicts of the 1920s, suffered the Great Depression, implemented the New Deal, and culminated in World War II victory that left the United States as a world superpower.
This period fundamentally redefined the federal government's role in the economy and society, transformed America from isolationist to internationalist, and reshaped the nation's racial, gender, and class dynamics—though often incompletely and with persistent inequalities.
🎯 Key Themes
- Progressivism: Reform movements addressing urban problems, business regulation, political corruption, social welfare
- Imperialism: U.S. acquired overseas territories; debated role as global power
- World War I: Reluctant entry; massive mobilization; failed peace; isolationist retreat
- 1920s Tensions: Modern vs. traditional values; consumerism, prohibition, immigration restriction
- Great Depression: Economic collapse exposed capitalism's vulnerabilities; mass unemployment
- New Deal: Unprecedented federal intervention; welfare state foundations; labor rights
- World War II: Total war; industrial mobilization; home front changes; atomic age begins
⚠️ AP Exam Context
- Period 7 carries 10–17% exam weight—substantial content requiring deep knowledge
- Understand government expansion: Progressive reforms → New Deal → WWII mobilization
- Master foreign policy shifts: Imperialism → WWI → isolationism → WWII internationalism
- Know social conflicts: Labor vs. capital, urban vs. rural, modern vs. traditional
7.2 Imperialism: Debates (WOR)
Reasons for American Imperialism
- Economic: Need for new markets, raw materials; foreign investment opportunities; surplus production
- Strategic: Naval bases, coaling stations; Alfred Thayer Mahan's The Influence of Sea Power Upon History argued for strong navy and overseas bases
- Cultural/Racial: "White Man's Burden"—duty to "civilize" non-white peoples; Social Darwinism applied to nations
- Religious: Spread Christianity to "heathen" peoples
- Nationalism: Compete with European powers; demonstrate national greatness
Debate Over Empire
Imperialists (Pro-Expansion)
- Leaders: Theodore Roosevelt, Alfred Thayer Mahan, Henry Cabot Lodge
- Arguments: Economic necessity, strategic security, moral duty, national prestige
- Support: Business interests, military leaders, many politicians
Anti-Imperialists
- Leaders: Mark Twain, Andrew Carnegie, William Jennings Bryan, Jane Addams
- Arguments: Contradicts democratic principles; exploitation is immoral; expensive; entangling alliances; racial mixing fears
- American Anti-Imperialist League: Founded 1898; opposed annexation of Philippines
🎯 Key Terms
- Imperialism: Policy of extending power through territorial acquisition or economic/political control
- Alfred Thayer Mahan: Naval strategist; advocated for strong navy and overseas bases
- White Man's Burden: Racist justification for imperialism
- Anti-Imperialist League: Opposed U.S. territorial expansion
⚠️ AP Exam Tips
- Multiple perspectives: Know both pro and anti-imperialist arguments
- Motivations: Economic, strategic, cultural, religious factors all played roles
- Contradiction: Democratic nation acquiring colonies contradicted founding principles
7.3 The Spanish–American War (WOR)
Causes & Events
- Cuban Rebellion (1895): Cuba fought for independence from Spain
- Yellow Journalism: Hearst (Journal) and Pulitzer (World) sensationalized Spanish atrocities; inflamed public opinion
- USS Maine (1898): Exploded in Havana Harbor; blamed on Spain (likely accidental); "Remember the Maine!"
- War Declaration: April 1898; "splendid little war" lasted 4 months
- Philippines: Commodore Dewey destroyed Spanish fleet at Manila Bay
- Cuba: Rough Riders (Teddy Roosevelt); San Juan Hill victory
Treaty of Paris (1898) & Consequences
U.S. Acquired: Puerto Rico, Guam, Philippines (for $20 million)
Cuba: Independent but under U.S. control (Platt Amendment—U.S. right to intervene)
Philippine-American War (1899-1902): Filipinos fought U.S. occupation; brutal conflict; 200,000+ Filipino deaths
Result: U.S. became imperial power with overseas territories
🎯 Key Terms
- Yellow Journalism: Sensationalist reporting to sell newspapers
- USS Maine: Ship explosion sparked war
- Platt Amendment: U.S. control over Cuba
- Philippine-American War: Brutal suppression of Filipino independence
7.4 The Progressives (PCE/GEO)
Who Were Progressives?
Middle-class reformers (journalists, social workers, professionals) who sought to address problems created by industrialization, urbanization, immigration. Believed government should actively solve social problems.
Key Reforms
Political Reforms
- Direct Primary: Voters choose party candidates
- Initiative/Referendum/Recall: Direct democracy tools
- 17th Amendment (1913): Direct election of senators
- 19th Amendment (1920): Women's suffrage
- Secret Ballot: Reduced corruption
Social Reforms
- Child labor laws: Restricted/banned child labor
- Factory safety: Triangle Shirtwaist Fire (1911) spurred reforms
- Temperance/Prohibition: 18th Amendment (1919) banned alcohol
- Public health: Pure Food and Drug Act, Meat Inspection Act
Business Regulation
- Trust-busting: Theodore Roosevelt broke up monopolies
- Federal Reserve (1913): Central banking system
- Clayton Antitrust Act (1914): Strengthened Sherman Act
- Federal Trade Commission (1914): Regulated business practices
Progressive Presidents
- Theodore Roosevelt (1901-09): "Square Deal"; trust-busting; conservation; consumer protection
- William Howard Taft (1909-13): Continued trust-busting but split Republican Party
- Woodrow Wilson (1913-21): "New Freedom"; Federal Reserve, FTC, Clayton Act; moral diplomacy
🎯 Key Terms
- Muckrakers: Investigative journalists (Ida Tarbell, Upton Sinclair, Jacob Riis)
- 17th Amendment: Direct election of senators
- 19th Amendment: Women's suffrage
- Federal Reserve: Central bank (1913)
- Triangle Shirtwaist Fire: 1911 factory fire; 146 dead; sparked reforms
7.5 World War I: Military and Diplomacy (WXT)
Path to War
Initial Neutrality: Wilson urged Americans to be "neutral in thought and deed"
Challenges to Neutrality:
- Economic Ties: U.S. loaned billions to Allies; sold war supplies
- British Propaganda: Portrayed Germans as barbaric "Huns"
- German Submarine Warfare: Unrestricted U-boat attacks on ships
Lusitania (1915): British passenger ship sunk by German U-boat; 128 Americans killed; outraged public but U.S. didn't enter war yet
Sussex Pledge (1916): Germany promised not to sink passenger ships without warning
Election of 1916: Wilson reelected on slogan "He Kept Us Out of War"
U.S. Entry (April 1917)
Immediate Causes
- Resumption of Unrestricted Submarine Warfare (1917): Germany broke Sussex Pledge; attacked all ships
- Zimmermann Telegram (1917): Intercepted German message proposing alliance with Mexico against U.S.; offered to return Texas, New Mexico, Arizona to Mexico
- Russian Revolution (March 1917): Fall of czar made Russia seem more democratic; easier to portray war as democracy vs. autocracy
Declaration: Wilson asked Congress for war; "make the world safe for democracy"
American Contribution to Allied Victory
Selective Service Act (1917): Drafted 2.8 million men; 2 million more volunteered
American Expeditionary Force (AEF): Led by General John J. Pershing; arrived in France 1917
Impact: Fresh American troops and resources tipped balance; helped break stalemate; Germany sought armistice
Armistice: November 11, 1918 (11/11 at 11 a.m.)—fighting ended
Wilson's Fourteen Points & Treaty of Versailles
Fourteen Points (1918)
Wilson's Vision: Blueprint for lasting peace
- Open Diplomacy: No secret treaties
- Freedom of the Seas: Neutral shipping protected
- Free Trade: Lower economic barriers
- Arms Reduction: Decrease military forces
- Self-Determination: National groups choose own governments
- League of Nations: International organization to prevent future wars (Point 14—most important to Wilson)
Treaty of Versailles (1919)
Big Four: Wilson (U.S.), Lloyd George (Britain), Clemenceau (France), Orlando (Italy)
Harsh Terms for Germany:
- War Guilt Clause: Forced Germany to accept blame
- Reparations: $33 billion payment to Allies
- Territory Loss: Germany lost colonies, land to neighbors
- Military Restrictions: Limited army size; no air force, submarines
Compromises: Allies rejected most of Fourteen Points; Wilson got League of Nations but accepted punitive terms
Senate Rejection
Opposition: Led by Senator Henry Cabot Lodge (Republican)
Concerns: Article X (collective security) threatened U.S. sovereignty; might drag U.S. into future wars
Wilson's Response: Refused to compromise; went on speaking tour to rally public; suffered stroke
Outcome: Senate rejected treaty twice (1919, 1920); U.S. never joined League of Nations; made separate peace with Germany
🎯 Key Terms
- Lusitania: 1915 sinking; 128 Americans killed
- Zimmermann Telegram: German proposal to Mexico; sparked U.S. entry
- Fourteen Points: Wilson's peace plan; emphasized self-determination
- League of Nations: International peacekeeping body; U.S. never joined
- Treaty of Versailles: Harsh peace treaty; blamed Germany
- Henry Cabot Lodge: Senator who led opposition to treaty
⚠️ AP Exam Tips
- Causes of entry: Submarine warfare + Zimmermann Telegram = immediate triggers
- Fourteen Points: Know key principles; contrast idealism with Versailles reality
- Senate rejection: Understand debate over Article X and sovereignty concerns
- Consequences: Treaty created conditions for WWII; U.S. returned to isolationism
7.6 World War I: Home Front (WXT)
Mobilization & Government Control
- War Industries Board: Coordinated production; set prices, allocated resources
- Food Administration: Herbert Hoover led; encouraged conservation ("Meatless Mondays")
- Fuel Administration: Controlled coal, oil distribution; "Heatless Mondays"
- Railroad Administration: Government took control of railroads
- War Finance: Liberty Bonds; increased taxes
Propaganda & Suppression
Committee on Public Information (CPI)
Led by: George Creel
Purpose: Shape public opinion; promote war effort
Methods: Posters, films, "Four-Minute Men" speeches; demonized Germans; encouraged patriotism
Civil Liberties Restricted
Espionage Act (1917): Outlawed interference with draft, military recruitment; up to 20 years prison
Sedition Act (1918): Banned "disloyal, profane, scurrilous, or abusive" language about government, flag, military
Impact: ~2,000 prosecuted; socialists, pacifists, German Americans targeted
Schenck v. United States (1919): Supreme Court upheld Espionage Act; "clear and present danger" test; limited First Amendment during wartime
Social Changes
Women
Workforce: Filled jobs vacated by men; factories, offices, streetcars
Recognition: Contributions helped win passage of 19th Amendment (1920)—women's suffrage
Great Migration
Movement: 500,000+ African Americans moved from rural South to Northern cities
Reasons: Jobs in war industries; escape Jim Crow; boll weevil destroyed cotton crops
Destinations: Chicago, Detroit, New York, Philadelphia
Impact: Changed urban demographics; racial tensions increased; race riots (East St. Louis 1917, Chicago 1919)
🎯 Key Terms
- War Industries Board: Coordinated war production
- Committee on Public Information: Propaganda agency
- Espionage & Sedition Acts: Limited free speech during war
- Schenck v. United States: Upheld speech restrictions; "clear and present danger"
- Great Migration: African Americans moved north for jobs
⚠️ AP Exam Tips
- Government expansion: War massively increased federal power over economy
- Civil liberties: War led to suppression of dissent; precedent for future conflicts
- Social change: War accelerated women's rights, Great Migration, racial tensions
7.8 1920s: Cultural and Political Controversies (MIG/ARC)
Modern vs. Traditional Values
The "New Woman"
Flappers: Young women who defied conventions—short skirts, bobbed hair, smoked, drank, danced
Greater Freedom: More women worked, attended college, participated in public life
Backlash: Traditional values defenders criticized changing morality
Prohibition (1920-1933)
18th Amendment (1919): Banned manufacture, sale, transportation of alcohol
Volstead Act: Enforcement legislation
Results: Widespread violation; speakeasies (illegal bars); organized crime (Al Capone); bootlegging
21st Amendment (1933): Repealed Prohibition—only amendment to repeal another
Scopes Trial (1925)
Issue: Tennessee law banned teaching evolution
John Scopes: Biology teacher prosecuted for teaching evolution
Lawyers: William Jennings Bryan (prosecution) vs. Clarence Darrow (defense)
Outcome: Scopes convicted but case highlighted science vs. religion debate; fundamentalism vs. modernism
Immigration Restriction
Emergency Quota Act (1921): Limited immigration to 3% of each nationality's 1910 U.S. population
National Origins Act (1924):
- Reduced quota to 2% of 1890 population (favored Northern/Western Europeans)
- Banned Asian immigration entirely
- Goal: Preserve "racial purity"; restrict "undesirable" immigrants
Impact: Drastically reduced immigration from Southern/Eastern Europe and Asia; reversed open-door policy
Racial & Social Tensions
Red Scare (1919-1920)
Fear of Communism: Russian Revolution sparked fear of radical takeover
Palmer Raids: Attorney General A. Mitchell Palmer ordered raids; arrested 6,000+ suspected radicals; many deported without trials
Sacco and Vanzetti (1920): Italian anarchists convicted of murder on weak evidence; executed 1927; case reflected nativist prejudices
KKK Revival
Growth: 4-5 million members by mid-1920s
Targets: Not just African Americans; also Catholics, Jews, immigrants, "immoral" behavior
Influence: Political power in some states (Indiana, Oregon)
Decline: Scandals, internal corruption reduced membership by late 1920s
Harlem Renaissance
Cultural Flowering: African American artistic and intellectual movement centered in Harlem, NYC
Writers: Langston Hughes, Zora Neale Hurston, Claude McKay, Countee Cullen
Musicians: Duke Ellington, Louis Armstrong; jazz became dominant American music
Significance: Celebrated Black culture; challenged stereotypes; influenced American arts
🎯 Key Terms
- 18th Amendment: Prohibition (1919-1933)
- Scopes Trial: 1925—evolution vs. fundamentalism
- National Origins Act: 1924—immigration quotas
- Red Scare: Anti-communist hysteria; Palmer Raids
- Harlem Renaissance: African American cultural movement
- Langston Hughes: Harlem Renaissance poet
⚠️ AP Exam Tips
- Cultural conflict: Modern urban values vs. traditional rural values
- Nativism resurged: Immigration restriction reflected racial/ethnic prejudices
- Harlem Renaissance: Know key figures and significance for Black cultural identity
7.9 The Great Depression (WXT)
Causes
- Stock Market Speculation: Buying on margin (borrowed money); inflated stock prices beyond real value
- Overproduction: Factories produced more than consumers could buy
- Unequal Wealth Distribution: Rich got richer; workers didn't earn enough to buy goods they produced
- Weak Banking System: Bank failures wiped out savings; no federal insurance
- Agricultural Depression: Farmers struggled since WWI; overproduction, debt, falling prices
- Global Economic Problems: International debt, tariffs reduced trade
The Crash & Depression
Black Tuesday (October 29, 1929): Stock market crashed; lost billions in value
Downward Spiral:
- Stock losses → reduced consumer spending → business failures → unemployment → less spending (cycle)
- 9,000 banks failed (1930-1933); depositors lost life savings
- 25% unemployment rate (13 million jobless) by 1933
- Industrial production fell 50%; farm income dropped 60%
Human Impact
- Homelessness: "Hoovervilles"—shantytowns of homeless people
- Hunger: Bread lines, soup kitchens; malnutrition
- Dust Bowl (1930s): Drought + poor farming practices = massive dust storms; "Okies" migrated to California
- Psychological Toll: Shame, despair, family breakdown
- Bonus Army (1932): WWI veterans marched on Washington demanding early bonus payment; Hoover ordered army to disperse them—violent eviction
Hoover's Response
Philosophy: Voluntary cooperation; "rugged individualism"; feared government handouts destroyed character
Actions:
- Urged business leaders to maintain wages, employment (didn't work)
- Reconstruction Finance Corporation (1932)—loaned money to banks, railroads, businesses (not individuals)
- Public works projects (but too small)
Criticism: Too little, too late; seemed uncaring; blamed for Depression
🎯 Key Terms
- Black Tuesday: October 29, 1929—stock market crash
- Buying on Margin: Purchasing stocks with borrowed money
- Hoovervilles: Shantytowns named mockingly after Hoover
- Dust Bowl: 1930s drought; ecological disaster
- Bonus Army: WWI vets demanding early payment; violently dispersed
⚠️ AP Exam Tips
- Multiple causes: Not just stock market crash; structural problems in economy
- Hoover's failure: Philosophy prevented effective response; set stage for New Deal
- Human cost: Understand Depression's devastating social impact
7.10 The New Deal (SOC)
FDR & First New Deal (1933-1935)
Election of 1932: Franklin D. Roosevelt defeated Hoover in landslide; promised "New Deal"
Philosophy: Government should actively address Depression through relief, recovery, reform
First 100 Days (March-June 1933): Congress passed 15 major laws
Banking & Finance
- Emergency Banking Act (1933): Closed banks for inspection; only sound ones reopened; restored confidence
- FDIC (Federal Deposit Insurance Corp.): Insured bank deposits up to $5,000; prevented bank runs
- Securities Exchange Commission (SEC): Regulated stock market; prevented fraud
Relief Programs (Alphabet Agencies)
- CCC (Civilian Conservation Corps): Employed young men in conservation projects; planted trees, built parks
- FERA (Federal Emergency Relief Admin): Direct relief to unemployed
- CWA/PWA (Civil Works Admin/Public Works Admin): Jobs building infrastructure
Recovery Programs
- AAA (Agricultural Adjustment Act): Paid farmers to reduce production; raise crop prices (later ruled unconstitutional)
- NIRA (National Industrial Recovery Act): Set production codes, minimum wages, maximum hours; guaranteed labor's right to organize (later ruled unconstitutional)
- TVA (Tennessee Valley Authority): Built dams for flood control, electricity; regional development
Second New Deal (1935-1938)
Major Programs
- WPA (Works Progress Admin, 1935): Employed 8 million in construction, arts projects
- Social Security Act (1935): Old-age pensions, unemployment insurance, aid to disabled; foundation of welfare state
- Wagner Act (1935): Guaranteed labor's right to organize, bargain collectively; created NLRB
- Fair Labor Standards Act (1938): Minimum wage ($0.25/hr), maximum hours (44/week), banned child labor
Opposition & Limits
From Right: Conservatives called New Deal socialist; violated free market; Supreme Court struck down AAA, NIRA
From Left: Critics said too timid; didn't redistribute wealth; Huey Long's "Share Our Wealth"; Father Coughlin's radio attacks
Court-Packing Plan (1937): FDR proposed adding justices to Supreme Court; failed but Court became more favorable
Limitations: Excluded many groups (agricultural workers, domestic servants—often Black); didn't end Depression (WWII did)
🎯 Key Terms
- New Deal: FDR's programs to address Depression (relief, recovery, reform)
- Alphabet Agencies: CCC, WPA, TVA, SSA, etc.
- Social Security: Old-age pensions; foundation of welfare state
- Wagner Act: Labor's right to organize
- FDIC: Insured bank deposits
⚠️ AP Exam Tips
- 3 R's: Relief (immediate help), Recovery (economic growth), Reform (prevent future depressions)
- Expanded federal power: New Deal fundamentally changed government's role in economy
- Legacy: Social Security, FDIC, labor rights endure; welfare state foundations
- Limitations: Didn't end Depression; excluded minorities; faced opposition
7.11 Interwar Foreign Policy (WOR)
Return to Isolationism
Post-WWI Disillusionment: Americans felt WWI was mistake; wanted to avoid future European entanglements
Washington Naval Conference (1921-1922): U.S., Britain, Japan agreed to limit naval armaments; ratio system for battleships
Kellogg-Briand Pact (1928): 62 nations renounced war as instrument of policy; no enforcement mechanism; symbolic only
Neutrality in Face of Aggression
Rise of Fascism & Aggression
- Italy: Mussolini invaded Ethiopia (1935)
- Germany: Hitler rearmed, remilitarized Rhineland, annexed Austria, seized Czechoslovakia
- Japan: Invaded Manchuria (1931), China (1937)
- Spanish Civil War (1936-1939): Germany and Italy supported Franco; U.S. remained neutral
Neutrality Acts (1935-1937)
Purpose: Prevent U.S. involvement in foreign wars
Provisions: Banned arms sales to warring nations; prohibited loans; Americans traveled on belligerent ships at own risk
Problem: Didn't distinguish between aggressors and victims; helped Axis powers
Shift Toward Intervention
Quarantine Speech (1937): FDR proposed "quarantining" aggressor nations; public reaction negative
Cash and Carry (1939): Modified neutrality—nations could buy arms if paid cash, carried in own ships; helped Britain
Destroyers-for-Bases Deal (1940): U.S. gave Britain 50 destroyers for naval base leases
Lend-Lease Act (1941): U.S. could lend/lease war materials to nations "vital to defense of U.S."; ended pretense of neutrality
🎯 Key Terms
- Isolationism: Policy of avoiding foreign entanglements
- Neutrality Acts: 1935-1937—tried to keep U.S. out of war
- Cash and Carry: Modified neutrality to help Allies
- Lend-Lease: Provided arms to Allies; ended neutrality
⚠️ AP Exam Tips
- Gradual shift: U.S. moved from strict neutrality to "arsenal of democracy"
- Debate: Isolationists vs. interventionists; public opinion shifted after fall of France
7.12 World War II: Mobilization (SOC)
Entry into War
Pearl Harbor (December 7, 1941): Japan attacked U.S. naval base in Hawaii; 2,400 Americans killed; 8 battleships damaged/destroyed
FDR's Speech: "A date which will live in infamy"
Declaration of War: U.S. declared war on Japan (December 8); Germany and Italy declared war on U.S. (December 11)
Impact: United American public; ended isolationism
Industrial Mobilization
War Production Board: Coordinated production; converted factories to war goods
"Arsenal of Democracy": U.S. industrial might produced massive amounts of weapons, planes, ships, supplies
Statistics: 300,000 aircraft, 86,000 tanks, 2,000 Liberty ships
Economic Impact: Ended Depression; full employment; GDP doubled
Home Front Changes
Women in Workforce
"Rosie the Riveter": Symbol of women war workers
Numbers: 6 million women entered workforce; filled factory jobs, clerical positions
After War: Many lost jobs to returning men; but women's roles permanently changed
African Americans
Double V Campaign: Victory abroad against fascism; victory at home against racism
Migration: Continued movement to Northern cities for war jobs
Military: 1 million served but in segregated units; Tuskegee Airmen proved Black pilots' abilities
Executive Order 8802 (1941): FDR banned discrimination in defense industries after A. Philip Randolph threatened march on Washington
Rationing & Sacrifice
Rationed Goods: Gasoline, meat, sugar, butter, tires, coffee
War Bonds: Raised billions through bond sales
Scrap Drives: Collected metal, rubber for war production
Japanese American Internment
Executive Order 9066 (1942): Authorized military to exclude people from "military areas"
Internment: 120,000 Japanese Americans (2/3 U.S. citizens) forcibly removed from West Coast; sent to camps in remote areas
Conditions: Barbed wire, armed guards; families lost homes, businesses, possessions
Korematsu v. United States (1944): Supreme Court upheld internment as military necessity
Legacy: Recognized as grave injustice; 1988 apology and reparations; worst violation of civil liberties in modern U.S. history
🎯 Key Terms
- Pearl Harbor: December 7, 1941—brought U.S. into WWII
- Rosie the Riveter: Symbol of women war workers
- Japanese Internment: 120,000 imprisoned; civil liberties violation
- Korematsu v. United States: Upheld internment
- Double V: Victory abroad and at home (against racism)
⚠️ AP Exam Tips
- Total war: Entire society mobilized; government control expanded dramatically
- Social change: Women, African Americans gained opportunities but faced continued discrimination
- Japanese internment: Know it was unjustified, racist policy; major civil liberties violation
7.13 World War II: Military (WOR)
Allied Strategy
"Europe First": Priority on defeating Germany before focusing on Japan
Grand Alliance: U.S., Britain, Soviet Union; Big Three: Roosevelt, Churchill, Stalin
Unconditional Surrender: No negotiated peace; Axis must surrender completely
European Theater
- North Africa (1942-1943): U.S. forces landed; defeated German Afrika Korps
- Italy (1943-1945): Invaded Sicily, then mainland; slow, costly campaign
- D-Day (June 6, 1944): Allied invasion of Normandy, France; largest amphibious assault in history; opened Western Front
- Battle of the Bulge (Dec 1944-Jan 1945): Last major German offensive; Allies held, then pushed toward Germany
- Soviet Advance: Red Army pushed from East; took Berlin
- VE Day (May 8, 1945): Germany surrendered; Hitler committed suicide
Pacific Theater
- Island Hopping: Strategy to capture key islands, bypass others; move closer to Japan
- Major Battles: Midway (1942—turning point), Guadalcanal, Iwo Jima, Okinawa
- Kamikazes: Japanese suicide pilots; desperate tactic
- Firebombing: U.S. bombed Japanese cities; Tokyo raid killed 100,000+
Atomic Bombs
Manhattan Project: Secret program to develop atomic bomb; led by J. Robert Oppenheimer
Truman's Decision: New president (FDR died April 1945) authorized use
Hiroshima (August 6, 1945): First atomic bomb dropped; 70,000+ killed instantly
Nagasaki (August 9, 1945): Second bomb; 40,000+ killed
Japanese Surrender (August 15, 1945): VJ Day; WWII ended
Justifications: Save American lives (invasion would cost 1 million casualties); force quick surrender; demonstrate power to Soviets
Controversy: Moral debate continues; civilian targeting; nuclear age began
Holocaust
Nazi Genocide: Systematic murder of 6 million Jews, millions of others (Roma, disabled, homosexuals, political prisoners)
U.S. Response: Initially slow to recognize scale; immigration restrictions prevented many from fleeing; didn't bomb concentration camps
Liberation: Allied forces liberated camps 1945; exposed horrors to world
🎯 Key Terms
- D-Day: June 6, 1944—Normandy invasion
- Island Hopping: Pacific strategy
- Manhattan Project: Atomic bomb development
- Hiroshima & Nagasaki: Atomic bombs ended war
- Holocaust: Nazi genocide; 6 million Jews murdered
⚠️ AP Exam Tips
- Atomic bomb debate: Know arguments for/against use; understand controversy
- Holocaust: Understand U.S. could have done more to help victims
- Total war: Civilian casualties, strategic bombing, genocide marked WWII
7.14 Postwar Diplomacy (WOR)
Wartime Conferences
Yalta Conference (February 1945): Roosevelt, Churchill, Stalin
- Divided Germany into occupation zones
- Stalin promised free elections in Eastern Europe (broke promise)
- USSR agreed to enter war against Japan
Potsdam Conference (July-August 1945): Truman, Churchill/Attlee, Stalin
- Tensions emerging; Truman tougher than FDR
- Confirmed German occupation plans
- Issued ultimatum to Japan
Creating Postwar Order
United Nations (1945)
Founding: 50 nations; headquarters New York
Purpose: Maintain peace, prevent future wars; learn from League of Nations' failure
Structure: General Assembly (all members); Security Council (5 permanent members with veto—U.S., USSR, Britain, France, China)
U.S. Membership: Senate approved; U.S. committed to internationalism
Economic Institutions
Bretton Woods Conference (1944):
- International Monetary Fund (IMF): Stabilize currencies, promote trade
- World Bank: Provide loans for reconstruction and development
- Established dollar as world reserve currency
Origins of Cold War
Soviet Expansion: USSR occupied Eastern Europe; installed communist governments; "Iron Curtain" descended
U.S. Response:
- Truman Doctrine (1947): U.S. would support free peoples resisting communism
- Marshall Plan (1948): $12 billion to rebuild Western Europe; prevent communist takeover
- NATO (1949): Military alliance against Soviet threat
Significance: WWII's end led immediately to Cold War; U.S. emerged as superpower committed to containing communism
🎯 Key Terms
- Yalta Conference: 1945—Big Three planned postwar world
- United Nations: International peacekeeping organization; U.S. joined
- Bretton Woods: IMF, World Bank created
- Truman Doctrine: Contain communism
- Marshall Plan: Aid to rebuild Europe
- NATO: Anti-Soviet military alliance
⚠️ AP Exam Tips
- Contrast with WWI: U.S. rejected League; joined UN; embraced internationalism
- Cold War origins: Wartime alliance quickly dissolved; ideological conflict emerged
- U.S. as superpower: WWII left U.S. economically, militarily dominant
7.15 Comparison in Period 7
Major Changes
- Government Expansion: Progressive reforms → New Deal → WWII mobilization = massive federal growth
- Foreign Policy: Isolationism → imperialism → WWI → isolationism → WWII → internationalism/superpower
- Economy: Federal regulation increased; welfare state created; economic crises led to government intervention
- Social: Women gained vote; migration transformed demographics; technology connected nation
- Warfare: Total war mobilized entire society; atomic weapons changed international relations
Continuities
- Racial Inequality: African Americans, other minorities still faced discrimination despite gains
- Gender Inequality: Women made progress but full equality remained elusive
- Civil Liberties Tensions: Wars led to suppression (Espionage Act, Japanese internment)
- Economic Inequality: Capitalism's problems persisted despite reforms
Key Comparisons
- Progressive Era vs. New Deal: Both expanded government to address problems; New Deal went further, created welfare state
- WWI vs. WWII: WWI reluctant entry, failed peace; WWII total commitment, successful postwar planning
- 1920s vs. 1930s: Prosperity vs. depression; cultural dynamism vs. despair; laissez-faire vs. intervention
- Isolationism vs. Internationalism: Rejected League; joined UN; became superpower
🎯 Synthesis Points
- Period 7 fundamentally redefined government's role in economy and society
- U.S. transformed from regional power to global superpower
- Economic crises and wars accelerated social change
- Tensions between liberty and security persisted through era
⚠️ AP Exam Tips
- Causation: Economic crises → government expansion; wars → social change
- Continuity & Change: Balance reforms with persistent inequalities
- Comparison: Use specific examples from different eras within Period 7
- Synthesis: Connect to Period 8 (Cold War continuation)
🎯 Master Unit 7 with These Strategies
📝 Practice Active Recall
Use our Period 7 flashcards covering Progressivism through WWII.
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💡 Key Study Tips
- Create timelines: Progressive Era → WWI → 1920s → Depression → New Deal → WWII
- Compare government responses: Progressive reforms vs. New Deal programs
- Understand foreign policy evolution: Imperialism → isolationism → internationalism
- Master constitutional amendments: 16th, 17th, 18th, 19th, 21st
- Connect to next period: WWII → Cold War beginnings
🌟 Remember: Period 7 transformed America from a regional power to a global superpower while expanding federal authority to address economic crises and wage total war. Master the connections between domestic reforms and international conflicts!