United States

Background

  • Isolationism (1920s–1930s):

    • After WWI, most Americans opposed foreign entanglements.

    • Neutrality Acts restricted arms sales/loans to warring nations.

  • Economic Context:

    • Great Depression weakened the U.S. in the 1930s.

    • Recovery accelerated with wartime production.

Entry into WWII

  • Pre-War Support for Allies:

    • 1941: Lend-Lease Act allowed aid to Britain, USSR, and China.

  • Pearl Harbor:

    • December 7, 1941: Japan attacked U.S. naval base at Pearl Harbor, Hawaii.

    • Over 2,400 Americans killed, much of Pacific Fleet damaged.

    • December 8, 1941: U.S. declared war on Japan.

    • Germany and Italy declared war on U.S. shortly after → full entry into WWII.

U.S. in the Pacific

  • Early Losses: Philippines fell to Japan; “Bataan Death March.”

  • Turning Point: Battle of Midway (1942) crippled Japanese fleet.

  • Island Hopping Strategy: Captured key islands while bypassing heavily fortified ones.

  • Kamikaze Resistance: Especially intense during battles like Okinawa (1945).

  • Atomic Bomb:

    • Hiroshima (Aug. 6, 1945) and Nagasaki (Aug. 9, 1945).

    • Japan surrendered Aug. 15, 1945.

U.S. in Europe

  • North Africa (1942–1943): Helped defeat Axis forces.

  • Italy Campaign (1943–1944): Pushed Axis out, Mussolini overthrown.

  • D-Day (June 6, 1944): Massive Allied invasion of Normandy, France.

  • Liberation: U.S. forces advanced through France and into Germany.

  • Endgame: Helped liberate concentration camps; met Soviet forces in central Europe.

Home Front

  • Wartime Economy:

    • Factories shifted to military production (“Arsenal of Democracy”).

    • Ended the Great Depression; unemployment dropped sharply.

  • Social Changes:

    • Women joined workforce (“Rosie the Riveter”).

    • Racial tensions persisted; African Americans pushed for “Double V” (victory against fascism abroad and racism at home).

    • Japanese Americans faced internment in camps (Executive Order 9066).

Legacy

  • Military: Emerged as a global superpower with unmatched industrial and military strength.

  • Political: Helped establish United Nations, Marshall Plan for European recovery.

  • Nuclear Age: First use of atomic weapons reshaped global power balance.