Even more significant was the tremendous increase in mobility. The war set families in motion, pulling them off of farms and out of small towns and packing them into large urban areas. Urbanization had virtually stopped during the Depression, but the war saw the number of city dwellers leap from 46 to 53 percent.
War industries sparked the urban growth. Detroit's population exploded as the automotive industry switched from manufacturing cars to war vehicles. Washington, D.C. became another boomtown, as tens of thousands of new workers staffed the swelling ranks of the bureaucracy. The most dramatic growth occurred in California. Of the 15 million civilians who moved across state lines during the war, over 2 million went to California to work in defense industries.
