What's Wrong with Preventive war? the Moral and Legal Basis for the Preventive Use of Force. - We find ourselves, it is widely claimed, in a new and unprecedented age of terrorism. The rules of the game, we are told, must change in order for us to respond to a new kind of threat from shadowy terrorist organizations not affiliated with any particular state, and with possible access to weapons of mass destruction. Among the most important of these proposed changes is that the United States should be able to wage a "preventive" war against its enemies--that is, to resort to military action before an attack has materialized, or indeed before it is even imminent. (1) In an interview on Meet the Press (February 8, 2004), President Bush explicitly rejected the imminence requirement: "I believe it is essential that when we see a threat, we deal with those threats before they become imminent. It's too late if they become imminent." The so-called Bush doctrine, articulated in the 2002 National Security Strategy, is widely seen as the blueprint of this new strategy. (2) It appears to adopt a radical innovation in permitting wars that are not merely in self-defense, but wars of prevention. This debate is of the utmost importance. It is fraught, however, with confusions and misunderstandings (not the least of which is the ambiguous terminology). In this essay, I will focus on one such misconception: the widespread perception that war is only justifiable in self-defense. On this view, preventive war is immoral and illegal as a matter of principle, as it is not a response to an actual or imminent attack. I will argue here that this assertion is quite mistaken, from a standpoint of both commonsense morality and the just war tradition. In the first two sections of this essay, I attempt to demonstrate the legitimacy of preventive war under just war doctrine and ordinary morality. In the final section, I address a major qualification to this position. The key issue in the debate over preventive war is not the morality of preventive war per se, but the question of the legitimate authorization for undertaking such a war--that is, the role of the United Nations in approving in advance the preventive use of military force. I conclude that only the Security Council has the authority to legitimize a preventive war, such as the one fought in Iraq.