5.4 World War II & the Home Front

From Neutrality to Intervention

Memories of World War I and the Depression made 1930s America deeply isolationist. Congress passed a series of Neutrality Acts to keep the U.S. out of foreign wars by banning arms sales and loans to belligerents. As Nazi Germany and Japan expanded, President Franklin Roosevelt gradually moved the country toward the Allies:

• 'Cash-and-carry' let warring nations buy U.S. goods if they paid cash and carried them in their own ships.
• The Lend-Lease Act (1941) allowed the U.S. to lend or lease war supplies to Britain and later the Soviet Union, making America the 'arsenal of democracy.'
• The Atlantic Charter (1941) set shared Allied war aims with Britain.

Regents items often ask what the shift from the Neutrality Acts to cash-and-carry and Lend-Lease shows: it demonstrates that the United States was abandoning strict neutrality and moving toward intervention on the Allied side even before it entered the war.

Pearl Harbor and Entry

On December 7, 1941, Japan launched a surprise attack on the U.S. naval base at Pearl Harbor, Hawaii, killing about 2,400 Americans. FDR called it 'a date which will live in infamy.' Congress declared war on Japan, and Germany and Italy then declared war on the United States. Unlike World War I, U.S. entry followed a direct attack on American territory.

The Home Front

World War II required total mobilization that finally ended the Depression by creating full employment.

Social effects were profound and heavily tested:

• Women entered defense plants in large numbers, symbolized by 'Rosie the Riveter.'
• African Americans pushed the 'Double V' campaign (victory abroad and against racism at home); A. Philip Randolph's threatened march pressured FDR to ban discrimination in defense industries.
• Mexican workers came north under the Bracero Program to fill agricultural labor shortages.

Japanese-American Incarceration

Wartime fear and prejudice led FDR to issue Executive Order 9066 in 1942, forcing about 120,000 Japanese Americans, most of them U.S. citizens, from the West Coast into inland incarceration (internment) camps. In Korematsu v. United States (1944), the Supreme Court upheld the removal as a wartime military necessity. The decision is now widely condemned as a grave civil-liberties violation; in 1988 Congress issued a formal apology and reparations. On the exam, Korematsu pairs with Schenck as an example of civil liberties restricted during wartime.

The Holocaust and Nuremberg

The Holocaust was Nazi Germany's systematic genocide of about six million Jews and millions of others. U.S. response during the war was limited; restrictive immigration quotas and other barriers kept many refugees out, and the War Refugee Board was created only late (1944). After the war, the Nuremberg trials prosecuted Nazi leaders and established the principle that individuals can be held accountable for crimes against humanity, even when 'following orders.' This precedent is a frequent Civic Literacy topic about human rights and international law.

The Atomic Bomb

The secret Manhattan Project developed the atomic bomb. After Germany surrendered (V-E Day, May 1945), President Harry Truman ordered atomic bombs dropped on Hiroshima and Nagasaki in August 1945, and Japan surrendered (V-J Day). The decision remains debated:

• Arguments for: it ended the war quickly and avoided a costly invasion of Japan that might have caused enormous casualties on both sides.
• Arguments against: it killed and injured well over 100,000 civilians, and critics argue Japan was near surrender or that a demonstration could have sufficed.

Global Outcome

World War II reshaped the world and the United States' place in it:

• The U.S. emerged as a military and economic superpower, its mainland untouched and its industry dominant.
• The United Nations was founded in 1945 to promote collective security and prevent future wars, this time with U.S. membership, unlike the League of Nations.
• The GI Bill funded veterans' education and home loans, expanding the middle class.
• The wartime alliance with the Soviet Union collapsed into the Cold War, the subject of the next chapter.

A strong exam response connects these outcomes: the war ended isolationism for good and set up decades of U.S. global leadership.

Common Exam Traps and Comparisons

Keep these distinctions sharp:

• WWI vs. WWII entry: the U.S. entered World War I over submarine attacks on shipping, but entered World War II after a direct attack on U.S. territory at Pearl Harbor. Do not swap the triggers.
• League vs. United Nations: the U.S. rejected the League of Nations after WWI but joined and helped found the United Nations in 1945. This reversal is a favorite comparison item.
• Korematsu paired with Schenck: both show civil liberties restricted in wartime (speech in WWI, freedom from detention in WWII), a recurring constitutional issue.
• The atomic-bomb debate is genuinely two-sided: a document-based question expects you to weigh 'ended the war and avoided invasion' against 'massive civilian deaths and Japan near surrender,' not to pick one 'correct' verdict.

Worked example: a source-reliability item might present a 1945 War Department statement defending the bomb. Ask about its purpose (to justify the decision to the public) and how that purpose limits its reliability for measuring the bomb's human costs, exactly the kind of point-of-view analysis the short-essay tasks reward. Tie the chapter together by noting that mobilization ended the Depression, the war destroyed isolationism, and the resulting superpower rivalry with the Soviet Union opened the Cold War.