| This dissertation reassesses the historical significance of raw materials to U.S. foreign relations by examining U.S. reliance on imported manganese ore, a ferroalloy indispensable to steel production. The study draws on research in Brazilian and U.S. archives, using Portuguese and English language sources. It analyzes how U.S. access to Brazilian manganese from World War I through the Korean War depended on webs of interest and conflict among U.S. steel firms, Brazilian capital, and political actors in both Brazil and the United States. It argues that internationalism triumphed in U.S. raw materials strategy, and that U.S. investment and assistance shaped Brazil's economy to protect U.S. access to manganese.;Blending insights from business, environmental, and diplomatic history, the study explores the unappreciated importance of manganese to the metallurgical evolution of steelmaking and to the making of U.S. foreign policy. It demonstrates that the growth of control over manganese by world steel interests, led by the U.S. Steel Corporation in Brazil, fueled a global surplus in the 1920s and placed economic and physical pressures on railroads that hauled manganese. As the manganese market collapsed in the 1930s, raw materials experts and defense officials tied to the U.S. steel industry agitated for policies that promoted access to foreign minerals, muting calls for national self-sufficiency. Through tariff policy, defense mobilization, stockpiling, technical assistance, and foreign lending, the Roosevelt and Truman Administrations embraced a global supply strategy, driven primarily by attention to manganese.;This study also establishes that U.S. involvement with Brazilian manganese influenced railroad, mining, and steel development in Brazil, and mediated that nation's dealings with the U.S. Export-Import Bank and World Bank. Although Brazilian elites found space to maneuver for economic independence, U.S. investment and aid during World War II and the early Cold War structured Brazilian transport options to privilege raw materials exports over industrial development. In highlighting the connections between infrastructure and manganese mining in Brazil, this dissertation reveals that the U.S. quest for manganese ore had a profound impact not only on U.S. foreign policy, but also on economic development in Brazil. |
