This article examines the debates around anarchist restriction that shaped the eventual passage of the Immigration Act of and argues that domestically oriented conceptions of national security are both challenged and constituted by transnational and international processes and currents. While discussions of transnational immigration control became important features of both scholarly discourse and popular debate in the wake of the terrorist attacks of , these discussions were not new. Similar debates about immigration policy, security, and civil liberties shaped discussions between the mid-s and early s, when an unprecedented wave of attacks against heads of state fed rumors of wide-ranging conspiracies, and reports of anarchist outrages in cities far and wide spread fear. Anarchist exclusion was far more than an example of a rising nativist tide raising all boats and excluding a widening spectrum of undesirable aliens. Such measures set the foundation for restriction based on political beliefs and associations that, over subsequent decades, would become critical to suppressing political dissent. Consequently, understanding how the fear of anarchist violence helped shape the contours of the domestic and diplomatic debates over anarchist restriction is critical as these old questions of transnational immigration control reemerge.