A sweeping, revisionist historical analysis of telecommunications networks, from the dawn of the republic to the 21st century. Telecommunications networks are vast, intricate, hugely costly systems for exchanging messages and information-within cities and across continents. From the Post Office and the telegraph to today's internet, these networks have sown domestic division while also acting as sources of international power. In Crossed Wires, Dan Schiller, who has conducted archival research on US telecommunications for more than forty years, recovers the extraordinary social history of the major network systems of the United States. Drawing on arrays of archival documents and secondary sources, Schiller reveals that this history has been shaped by sharp social and political conflict and is embedded in the larger history of an expansionary US political economy. Schiller argues that networks have enabled US imperialism through a a recurrent "American system" of cross-border communications. Three other key findings wind through the book. First, business users of networks--more than carriers, and certainly more than residential users--have repeatedly determined how telecommunications systems have developed. Second, despite their current importance for virtually every sphere of social life, networks have been consecrated above all to aiding the circulation of commodities. Finally, although the preferences of executives and officials have broadly determined outcomes, these elites have repeatedly had to contend against the ideas and organizations of workers, social movement activists, and other reformers. This authoritative and comprehensive revisionist history of US telecommunications argues that not technology but a dominative--and contested--political economy drove the evolution of this critical industry.