President Franklin Delano Roosevelt wasn't the first to call America—and Detroit, specifically—"The Arsenal of Democracy," but he popularized the phrase during his famous "fireside chats." And for once, political rhetoric didn't outstrip reality: During the 1940s, Detroit's factories went from manufacturing cars to building tanks, bombers, army trucks, ordnance—in short, arming U.S. forces for battle in World War II. Pictured: Workers build tanks on the assembly line at a Chrysler plant.
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