Mobilizing for the Second World War

The New Deal had eased the Depression but never ended it. War spending did, because war gave government a blank check and a single clear goal: produce. Washington created agencies like the War Production Board to direct factories toward tanks, planes, and ships instead of cars and refrigerators. Companies converted assembly lines almost overnight. Ford built B-24 bombers at Willow Run. The result: roughly 300,000 aircraft and about 2,700 Liberty ships built in under four years. Liberty ships show the method best. Instead of building a hull piece by piece on one slow timeline, shipyards prefabricated sections elsewhere and welded them together on the ways, cutting construction from months to weeks. That is mass production applied to an industry that had never been organized around speed before.

Mobilization also remade the workforce. With millions of men in uniform, women took factory jobs once closed to them, symbolized by Rosie the Riveter, and Black southerners migrated north and west to work in defense plants in cities like Detroit and Los Angeles, continuing the Great Migration begun in the first world war. These shifts did not erase discrimination, but they cracked old barriers and set up postwar fights over civil rights and gender roles.

The same wartime fear that built ships also justified injustice. After Pearl Harbor, Executive Order 9066 authorized the forced removal of roughly 120,000 Japanese Americans, most of them citizens, into internment camps. The Supreme Court upheld this in Korematsu v. United States, showing how national emergency could override constitutional rights even with the courts' approval.