In an obscure paragraph of a package of immigration reforms adopted in 1996, the United States government committed itself to developing “an automated system to track the entry and exit of all non-citizens, thus providing a way of identifying immigrants who stay longer than their visas allow.” At the time that the legislation was supposed to be put into effect, however, some in the government came to regard this measure as likely to cause undue complications for millions of border-crossers, and the implementation of the law was postponed for two and a half years. The postponement was also deemed advisable in part because the Immigration and Naturalization Service, the agency mandated to design the system, was far from having amassed the technology “to process information estimated to be so vast that in one year it would exceed all the data in the Library of Congress.” Clearly, this program would be an enormous and unprecedented undertaking.

This book examines some of the background to such efforts to identify and track the movements of foreigners. The study concentrates on the historical development of passport controls as a way of illuminating the institutionalization of the idea of the “nation-state” as a prospectively homogeneous ethnocultural unit, a project that necessarily entailed efforts to regulate people's movements. Yet because nation-states are both territorial and membership organizations, they must erect and sustain boundaries between nationals and non-nationals both at their physical borders and among people within those borders.