Preemptive Force

Emergency measure taken with the aim of preventing an imminent, and otherwise unavoidable, attack. The idea of preemptive force is usually employed in a military context, whereby a state claims its right to launch an offensive on a potential enemy before that enemy has had the chance to actually implement a plan of attack. The advantage of preemptive strike is rather obvious; by being the first to act decisively, one renders the enemy unable to carry out aggressive intentions. There are also several disadvantages, however, to this strategy. For one, the threatened state might be wrong in its assessment of the threat and launch an unwarranted destructive attack. Second, the use of a preemptive force by one state might set a precedent that would lead to widespread abuse of the preemptive option.

Basic Conditions

Although scholars and politicians sharply disagree on the ultimate legitimacy of the use of preemptive force, most do tend to agree on several fundamental prerequisites for a specific attack to even be conceived as a potentially justifiable preemptive strike. First, the attack has to come as a reaction to a perceived threat that is both absolutely credible and immediate. Second, the state that reacts to the threat needs to be sure that a preemptive attack is the only effective way to defend itself. Third, the preemptive action needs to be proportionate in scope and potential for destruction with the perceived threat.

One problem, however, is the ambiguous concepts on which these three conditions rest. How credible is credible enough? What does immediate mean? What are the measurements by which one assesses the [Page 592]potential for destruction of an event that has not yet taken place?

Interpreting the UN Charter

Article 51 of the UN Charter is widely perceived as being extremely relevant to the question of preemption, as it explicitly protects “the inherent right of individual or collective self-defense if an armed attack occurs against a member of the United Nations.”

Opponents of the strategy of preemption argue that the article clearly conditions a defensive action on the previous occurrence of an attack, not on the perception of the possibility for an attack. Supporters of the strategy, however, point out that Article 51 does not use the phrase “if and only if an armed attack occurs,” therefore leaving the door open for other instances when preemptive force can be used legitimately.

In 2002, President George W. Bush presented the American people with a new National Security Strategy. According to it, the rise of terrorism and the increase in the availability of weapons of mass destruction have changed the international climate to such an extent that the United States now reserves the right to launch a preemptive attack on an enemy “even if uncertainty remains as to the time and place of the enemy's attack.” That right was invoked most recently in the Iraq War of 2003, and it remains a highly controversial concept.