A history with surprising new revelations about the depths of government surveillance and constitutional rights abusesIn the nineteenth and twentieth centuries, anarchist and socialist political movements spurred the expansion of nascent US federal surveillance capabilities. But it was the ensuing, decades-long persistent exaggerations of domestic political threats that drove an exponential increase in the size and scope of unlawful government surveillance and related political repression, which continue to the present. The Triumph of Fear is a history of the rise and expansion of surveillance-enabled political repression in the United States from the 1890s to 1961. Drawing on declassified government documents and other primary sources, many obtained via dozens of Freedom of Information Act lawsuits and analyzed for the first time, Eddington offers historians, legal scholars, and general readers surprising new revelations about the depths of government surveillance programs and how this domestic spying helped fuel federal assaults on free speech and association.