Preemption and the War on Terror: Morality, law, and the use of force

The threat of global terrorism realized on September 11 th requires a careful and limited expansion of the right to use preemptive force. The standard governing preemption since at least the end of the Second World War, with its principal requirement of an imminent armed attack, can no longer provide states with the security they require. Efforts to revise the standard, however, have failed on two points. First, revisionists have failed to show how an expansion of the right is consistent with underlying moral norms that shaped the standard in the past. Second, the United States government has rejected the settled standard without offering any concrete alternative in its place. An important resource for revising the standard of preemption, and the focus of this work, is the moral tradition on the just war. Augustine, followed by Aquinas, established criteria for deciding when armed force is morally justifiable. In the sixteenth century, Vitoria and other neo-Scholastics applied this moral framework directly to the issue of preemption. A standard evolved in the writings of Grotius, Pufendorf, Vattel and other theorists. At the same time, Machiavelli and Hobbes articulated a rival and permissive tradition on the use of force. Although the nineteenth century witnessed the triumph of the Hobbesian tradition, the just war standard was not altogether eclipsed. Rather, its norms reappeared with the adoption of the U.N. Charter in the middle of the twentieth century. The customary law governing the use of preemption, most often identified with the standard articulated by Webster in the Caroline Affair, draws directly on this moral tradition. A careful understanding of just war thought as it developed from Augustine onwards is valuable on at least two counts. First, it suggests a rationale, consistent with underlying moral commitments shaping the tradition in the past, for moving away from a standard primarily centered upon imminence. Moreover, it also suggests several criteria that might govern the decision to use preemptive force, if imminence can no longer hold the singular importance it did in the past.