The metaphor of the balance has long dominated national security law and policy. As Richard Posner has explained, one side of the balance “contains individual rights, the other community safety, with the balance needing and receiving readjustment from time to time as the weights of the respective interests change. The safer we feel, the more weight we place on the interest in personal liberty; the more endangered we feel, the more weight we place on the interest in safety, while recognizing the interdependence of the two interests.” While policymakers have debated the relative weight states should give to civil liberty concerns and public security concerns in various contexts, few question the general balance metaphor that structures these debates. By all accounts, interest balancing has provided the primary model for making national security law and policy worldwide since September 11, 2001.
