The Implications of Preemptive and Preventive War Doctrines: A Reconsideration

Preemption has been, and remains, a leading concept of this decade. But despite its ubiquity in public discourse and its policy relevance, it is a source of great confusion. The term is misused, in some cases deliberately one suspects, but it must be admitted that strategic theorists have offered very little worthwhile reading on the subject. This monograph clarifies the meaning of preemption and distinguishes it from prevention and precaution. It critically reviews the principal charges levelled against preventive warfare and uses that analysis to provide at least the bare bones of strategic theory, more strictly of an alternative to theory relevant to such warfare. The analysis concludes with a set of policy and strategy relevant implications for the United States. Preemption is not controversial; legally, morally, or strategically. To preempt means to strike first (or attempt to do so) in the face of an attack that is either already underway or is very credibly imminent. The decision for war has been taken by the enemy. The victim or target state can try to disrupt the unfolding assault, or may elect to receive the attack before reacting. In truth, military preemption will not always be feasible. By way of the sharpest contrast, a preventive war is a war of discretion. It differs from preemptive war both in its timing and in its motivation. The preemptor has no choice other than to strike back rapidly; it will probably be too late even to surrender. The preventor, however, chooses to wage war, at least to launch military action, because of its fears for the future should it fail to act now. In other words, the preventor strikes in order to prevent a predicted enemy from changing the balance of power or otherwise behaving in a manner that the preventor would judge to be intolerable. Naturally, the more distant the anticipated menace, the greater the degree of guesswork as to the severity and timing of the danger. A precautionary war is one waged not out of strong conviction that a dangerous threat is brewing in the target state, but rather because it is suspected that such a threat might one day emerge, and it is better to be safe than sorry. Put in the vernacular, preventive war, the real subject of this monograph, refers to the option of shooting on suspicion. In an age of weapons of mass destruction (WMD), it could be too late to shoot if one waits for suspicion to be verified by hostile behavior. The official American attitude toward preemption has fluctuated between the admirable declarations of principle by two of its outstanding lawyers: Daniel Webster in 1842 and Elihu Root in 1914. Webster insisted that preemptive action is justified only in the event of a threat that is so imminent that there is no time for other measures. Root took the far more expansive and flexible view that preemptive action must be permitted on a timeline that allows the victim state to take precautions. In effect, Root amended Webster by claiming the legality of a decision to wage preventive war in order to forestall the maturation of the menace. This is not preemption, it is prevention. Contrary to the impression one might derive from the scale and intensity of the legal debate, it happens to be the case that there really is no legal issue about this subject. International law, in the form of the United Nations Charter, recognizes the inherent right of selfdefense by states, and it does not oblige a victim state to wait passively to be struck by an aggressor, although it appears to do so—it is a matter of interpretation. In short, preventive action by way of anticipatory selfdefense is legal, or legal enough. Understandably, this permissive interpretation of the license granted by the right of self-defense is open to criticism. In effect, it means that there is no legal constraint on a state’s right to resort to force.