World War II: Mobilization, 1941-1945

By the end of this lesson, students will be able to:

• Account for how mass mobilization for the Second World War helped end the Great Depression and built the country's strong industrial base into the engine of Allied victory.
• Explain how wartime federal agencies, including the War Production Board, the Office of Price Administration, and the Office of War Information, reorganized civilian life around war production.
• Account for the wartime experiences that opened questions about American values, including the internment of Japanese Americans, the Double V campaign, and the Zoot Suit Riots of 1943.
• Describe how women, African Americans, and Mexican workers entered defense industries and agriculture under Executive Order 8802 and the Bracero Program.
• Use Skill 1.B (Causation) to identify a wartime mobilization process and account for its postwar consequences, including the GI Bill and the population shift to the West Coast and Sun Belt.

The American home front did not begin on December 7, 1941. The Selective Training and Service Act of September 1940, the first peacetime draft in American history, registered sixteen million men in the year before Pearl Harbor and put roughly nine hundred thousand of them into uniform by the end of 1941. Lend-Lease, signed in March 1941, was already moving British orders through American factories. What changed in December 1941 was the scale of federal authority. Within seven weeks of the Japanese attack, Franklin Roosevelt had created the War Production Board, the Office of Price Administration, and the framework of an internment apparatus that would empty the Pacific Coast of its Japanese American population (KC-7.3.III.B).

The economic story is the most direct one. The War Production Board, headed by the Sears Roebuck executive Donald Nelson, converted civilian factories to military output: Detroit's automobile lines stopped producing cars in February 1942 and turned out tanks, aircraft, and trucks for the rest of the war. Federal contracts ran disproportionately to the largest industrial firms in the country, but the contracts touched every region. The Office of Price Administration capped prices and rolled out a national rationing apparatus that issued books of stamps for gasoline, sugar, meat, butter, coffee, shoes, and rubber tires, all in scarce wartime supply. The federal government covered nearly half the war's cost through borrowing, and war bonds sold to ordinary households absorbed a large share of that debt. The Office of War Information coordinated wartime propaganda, producing posters, newsreels, and radio scripts that explained rationing, recruited workers and soldiers, and stitched the federal request for sacrifice to the household calendar. Roughly sixteen million Americans served in the armed forces between 1941 and 1945. Industrial mobilization put the rest of the country to work: the unemployment rate, which had stood near fifteen percent at the end of 1940, fell to roughly one percent by 1944, and the Great Depression ended in fact if not yet in textbook (KC-7.3.III.B).

The labor force that filled the new factories was not the labor force of 1939. With sixteen million men in uniform, defense plants drew on workers the prewar economy had largely excluded. Roughly six million American women entered the paid workforce during the war, many of them in heavy industry: at the Willow Run bomber plant near Detroit, at the Kaiser shipyards in Richmond, California, at ordnance and aircraft plants from Long Island to Wichita to Seattle. The figure of Rosie the Riveter, named in a 1942 song and rendered most famously by Norman Rockwell on a 1943 Saturday Evening Post cover and by J. Howard Miller on the Westinghouse "We Can Do It!" poster, became the cultural shorthand for women's wartime industrial labor. Black workers pushed into defense employment over employer and union resistance. In June 1941, with American war production already accelerating, A. Philip Randolph of the Brotherhood of Sleeping Car Porters threatened a march of one hundred thousand African Americans on Washington unless the federal government barred racial discrimination in defense plants. To call it off, Roosevelt issued Executive Order 8802, banning racial discrimination in federal defense work, and created the Fair Employment Practices Committee (FEPC) to investigate complaints. The order had limited enforcement power, but Black industrial employment in defense plants more than doubled between 1942 and 1945, and the FEPC became a template for later federal civil-rights agencies.

The wartime farm and rail labor pool drew across the southern border. The Bracero Program, established by a bilateral agreement between the United States and Mexico in August 1942, brought Mexican guest workers into American agriculture and railroad maintenance for the duration of the war and beyond. Roughly four and a half million Mexican workers entered the United States under Bracero contracts before the program closed in 1964; their labor was concentrated in the irrigated valleys of California, Texas, and the desert Southwest. The program supplied the wartime crops that fed the Allied armies, and it laid the legal and demographic groundwork for the postwar Mexican-American workforce that would shape the Sun Belt economy for the next two generations (KC-7.2.II.D).

The most visible failure of the wartime state was directed against the country's own Japanese American population. On February 19, 1942, Roosevelt signed Executive Order 9066, which authorized the War Department to designate military exclusion zones along the Pacific Coast. Under that authority, the Western Defense Command forcibly removed roughly one hundred and twenty thousand people of Japanese ancestry, two thirds of them American citizens, from California, Oregon, and Washington. They were held in ten War Relocation Authority camps in inland states for the duration of the war: Manzanar, Tule Lake, Heart Mountain, Topaz, Minidoka, and the others. Property was sold under duress; businesses, farms, and homes were lost. In Korematsu v. United States (December 1944), the Supreme Court upheld the military exclusion order by a vote of six to three. Forty-four years later, the Civil Liberties Act of 1988 acknowledged the program as a wartime injustice and authorized a formal federal apology and reparations payments to surviving internees (KC-7.3.III.C.i).

Race relations on the home front did not stop at the camp gate. In June 1943, in Los Angeles, eleven days of street violence between white sailors and Mexican American youths wearing the high-waisted, broad-shouldered zoot suit produced what came to be called the Zoot Suit Riots. The Los Angeles Police Department arrested the Mexican American victims rather than the servicemen attacking them, and the Hearst press treated the violence as a public-order story rather than a racial one. Similar violence broke out in Detroit later in the same month, where thirty-four people died in two days of rioting between white and Black residents. The Double V campaign, launched by the Pittsburgh Courier in February 1942 and quickly adopted across the Black press, demanded victory abroad against the Axis powers and victory at home against the racial discrimination that produced the Detroit riot, the segregated Army, the redlined defense-housing projects, and the white primary. The campaign drew on the same rhetoric Roosevelt had used to justify the war, and the gap between rhetoric and treatment became, in turn, the central argument the postwar civil-rights movement would carry into the 1950s (KC-7.3.III.C.i).

The most expensive single project of the war was hidden. The Manhattan Project, begun in 1942 under the direction of General Leslie Groves and the physicist J. Robert Oppenheimer, employed roughly one hundred and thirty thousand workers across secret installations at Los Alamos, Oak Ridge, and Hanford. Its budget reached approximately two billion dollars, equivalent to roughly thirty billion in today's currency. The Manhattan Project succeeded in July 1945, when the Trinity test detonated the first atomic device in the New Mexico desert. The bombs that followed in August 1945 over Hiroshima and Nagasaki are the subject of Topic 7.13, but the home-front mobilization that produced them belongs to this lesson.

The mobilization left two postwar legacies the AP exam returns to most often. The GI Bill (the Servicemen's Readjustment Act), signed by Roosevelt in June 1944, provided returning veterans with federally guaranteed home loans, low-cost business loans, and tuition for college and vocational training. Roughly eight million veterans used GI Bill education benefits in the decade after the war, and the program built the postwar middle class on a scale no earlier American social legislation had attempted. The GI Bill's benefits, however, were administered through state and local institutions that excluded most Black veterans from the housing and education advantages it offered, a fact that helps account for the postwar racial wealth gap. The second legacy is geographic. Wartime production drew workers to the West Coast aircraft and shipbuilding centers and to the Sun Belt aluminum, refining, and synthetic-rubber plants. California's population grew by nearly forty percent during the war; the demographic geography that produced postwar suburbia, postwar Cold War defense spending, and the postwar political realignment of the South and West was already visible by V-J Day (KC-7.3.III.B).

The four sources below sample the home front from four different angles: the executive declaration, the order that authorized internment, the Court that upheld it, and the propaganda image that became the war's most-copied icon.

1. (Causation) Account for how mass mobilization for the Second World War ended the Great Depression. Identify two specific federal mechanisms that connected war production to civilian employment, and assess which was more consequential.
2. (Continuity and Change) Compare the federal government's relationship to the American economy in 1939 with the relationship in 1945. Identify two continuities with the New Deal and one significant departure produced by wartime mobilization.
3. (Causation) A. Philip Randolph's threatened March on Washington in June 1941 produced Executive Order 8802 without ever taking place. Account for the political conditions that made the threat sufficient, and explain how the order's limits anticipated later civil-rights legislation.
4. (Comparison) Compare the wartime experience of Japanese Americans on the Pacific Coast with the wartime experience of Mexican Americans in the Bracero Program. What does the comparison reveal about the racial limits of the wartime federal state?
5. (Continuity and Change) The GI Bill of 1944 is often cited as the most consequential domestic legislation of the twentieth century. Identify two ways the bill shaped postwar American society, and account for one population it excluded in practice.

Draft alignment — pending educator review. AP USH codes correspond to the official College Board Course and Exam Description (Effective Fall 2023, Version 1). Statements below are paraphrased in the CountryReports voice; refer to the College Board's published CED for verbatim wording.