This dissertation explores how American domestic reformers of the late nineteenth and early twentieth centuries, influenced by William James's pragmatism, developed a political ethics that provided a new template for U.S. foreign relations and produced the first truly internationalist foreign-policy doctrine in American history. The doctrine developed in three distinct stages. First, avowedly pragmatist reformers applied Jamesian philosophical ideas and methods to domestic and then international problems. Second, Woodrow Wilson adopted, albeit falteringly, a similar approach to both domestic policy and foreign policy in Asia, Latin America, and Europe. Finally, Wilson's postwar plan for a League of Nations incorporated pragmatist perspectives on human interdependence, political experimentation, and the mediatory power of deliberative discourse to a degree not previously acknowledged by historians. Along the way, Wilson at times perverted the pragmatist progressives' project of expanding the social and economic scope of democracy through his imperialist adventures in Latin America. Yet some of these blunders, notably in Mexico, helped sharpen Wilson's pragmatic vision of a new global order predicated on international interdependence and reciprocal obligations between states.

Ultimately, Wilson's vision for a world order based upon a partial but genuine relinquishment of sovereignty by even the most powerful nations--including the United States--was more radical than any seriously pursued by policy makers before or since. Yet Wilson's plan was in many ways practical as well as radical. He abjured ideological dogma and envisioned a flexible, adaptive, democratic organization of states, capable of assimilating lessons of success and failure, as the crucial structure sustaining an orderly but ever-changing international society. By revealing pragmatism, progressivism, and internationalism as organically related states of thinking, culminating in an attempt to relate the states of the world more organically, this dissertation challenges prevailing views of early twentieth-century American political thought, affirms the importance of the links between domestic and foreign affairs as well as between intellectual and political history, and seeks to encourage a more general reevaluation of the options available to societies with democratic aspirations both at home and abroad.