We have been told on countless occasions that we are at war against international terrorism. Casualties, both civilian and military, mount in this war-the most noteworthy terrorist attack produced more casualties than the attack on Pearl Harbor. Our military forces are engaged in a multitude of ways, from direct combat overseas, to advising friendly governments and their militaries, to assisting domestic law enforcement.1 We are advised that this war, like the Cold War before it, will be a long and difficult struggle.
But if we are at war, it is a very different kind of war. Our enemies are not the soldiers of a state. In fact, following the military defeat of the Taliban and al Qaeda in Afghanistan, there is no state in the world that overtly claims to be anything other than our ally in this struggle. Al Qaeda's goals are not to conquer territory, control resources, nor even further traditional political or ideological purposes. They seek weapons of mass destruction-not as deterrents against the actions of other states-but for use at times and in places calculated to cause maximum destruction and horror. The enemy "soldiers" wear no uniforms, have no fixed bases, and are themselves essentially stateless.2
Yet those with whom we are at war must operate from somewhere. They must store weapons somewhere; they must train and house their fighters somewhere; they must develop their plans somewhere; and their leaders must sleep somewhere. These activities must occur on the territory of some state. Moreover, they must be supported from somewhere. Their weapons must come from somewhere, their funds must come from somewhere, and their supplies must come from somewhere.
How can states counter this new threat? If a country is to attack nonstate actors, what is the appropriate predicate to conduct that attack on the territory of another state? Is the current state of international law adequately addressing the relatively recent phenomenon of nonstate terrorist organizations that have many of the indicia of statehood? What are the legal theories that support possible state responses to varying degrees of terrorism? Do states have responsibilities and duties to counter terrorist acts, and do other states have a legal basis upon which they can effectively act if these duties are breached? This Article addresses these questions and submits that, in fact, current international law provides a basis for state actions that respond effectively to terrorist acts. However, this Article argues that the precepts of state responsibility and the commonly accepted 19th century definition of anticipatory self-defense must be adapted to recognize the technological realities of the 21st century.
II. TWO APPROACHES TO TERRORISM
A state may use two possible legal theories in responding to terrorist acts: (1) a law enforcement approach or (2) a use of armed force (conflict management) approach. Until recently, the law enforcement approach has predominated.3 This approach considers terrorist events as purely criminal acts to be addressed by various civil government functions-essentially the domestic criminal justice system and its components: police, investigators, prosecutors, defense attorneys, judges, juries, appellate courts, and a corrections system. If successful, actors are identified, prosecuted, convicted, and punished. As there is no agreed upon definition of terrorism,4 the crimes charged-murder, kidnapping, hijacking, and arson-reflect domestic criminal law with little or no reference to the terrorist motives of the defendants or the international character of their organizations.
Some argue that the possibility of dismissed charges or acquitted defendants should result in the abandonment of the law enforcement approach. They believe that only the use of armed force will result in the degree of decisive action that will minimize the likelihood that offenders will go unpunished. …