INTRODUCTION: LINKING PUBLIC HEALTH AND NATIONAL SECURITY
In the not too distant past, attempts to connect public health and national security would have raised eyebrows and perhaps condescending sympathy from experts in both areas. The discipline of public health focuses on "what we, as a society, do collectively to assure the conditions in which people can be healthy."1 Although public health has long been an issue in international relations,2 public health studies have had a strong domestic focus. For example, public health law texts "in the United States from the twentieth century . . . contain little or no discussion of international considerations."3 Even when public health analysis ventures beyond the domestic to consider international aspects of population health, the issues examined, such as the cross-border transmission of infectious diseases,4 do not typically involve the problems at the heart of national security studies, such as the military balance of power. By contrast, the study of national security traditionally has concentrated analysis on external threats, mainly of a military nature, to a country's interests, security, and survival.5 Historically, analysts in this field have not studied public health problems as national security threats.
Arguments linking public health and national security have, however, become frequent in the past seven to eight years.6 Increased concerns about the proliferation of biological weapons and the potential for bioterrorism have brought national security and public health closer together than has traditionally been the case. The perpetration of bioterrorism in the United States in October 2001 brought the public health-national security connection more prominence and policy attention. This Article examines the linkage of public health and national security in order to understand the origins, nature, and future implications of this new development in the foreign policy arena.
Analyzing the public health-national security linkage is important for many reasons. This linkage connects, for example, public health with developments in the area of security studies7 and debates about the nature and meaning of national security.8 Different perspectives on what "security" means compete for attention, and the literature that brings public health and national security together forces those in public health to contemplate these different perspectives and how they relate to the public health mission of protecting population health. The linkage also challenges those studying national security to consider issues, such as the relationship of public health to a state's material capabilities, previously alien to national security debates. The different perspectives on the meaning of security further relate to larger theoretical concepts concerning the structure and dynamics of international relations. The linking of public health and national security thus raises deeper theoretical issues and controversies about world politics in the global era.
First, using the literature that posits and analyzes the public health-national security linkage, this Article examines the emergence of the concept of "public health security," which refers to the policy areas in which national security and public health concerns overlap (Part I). Delineating the overlap requires defining both "public health" and "national security," which proves difficult with both terms. Second, in connection with defining security, this Article examines four different conceptions of security-the realpolitik, common, human, and ecological security perspectives-and how these conceptions produce different visions of public health security (Part II). This analysis focuses on the two dominant themes in the literature on the public health-national security linkage: the threats posed by emerging and reemerging infectious diseases and biological weapons. Contrary to most of the literature on the public health-national security linkage, I argue that the realpolitik security perspective is relevant to thinking about how to conceptualize public health security. …