When private incentives are insufficient, a big push by government may lead to industrialization. This article uses mobilization for WWII to test the big push hypothesis in the context of postwar industrialization in the American South. Specifically, I investigate the role of capital deepening at the county level using newly assembled data on the location and value of wartime investment. Despite a boom in manufacturing activity during the war, the evidence is not consistent with differential postwar growth in counties that received more investment. This does not rule out positive effects of mobilization on firms or sectors, but a decisive role for wartime capital deepening in the South's postwar industrial development should be viewed more skeptically.