Begin with Sen. Levin, who has been one of the most cogent critics. In a recent television appearance, the senator acknowledged that Saddam Hussein has violated Resolution 1441, the "final opportunity" offered him by the Security Council. He nevertheless argued that the United States should go along with proposals for continued inspections, because any action without additional approval from the United Nations would be wrongly "unilateral." The first part of this argument makes the least sense: By its logic, the 1999 intervention in Kosovo, which Sen. Levin supported, also would have been "unilateral" and thus unjustified. In this case, the Security Council has passed a specific resolution providing for "serious consequences." The problem is not that authority to act is lacking but that a handful of countries are seeking to block the implementation of a unanimously approved resolution. If they succeed, they, and not the Bush administration, will have subverted the Security Council.

Sen. Levin's larger argument, that intervention in Iraq would be too risky without a broad alliance, is stronger. Yet it now appears that at least two dozen nations, including a decisive majority of the NATO alliance, will back the United States. The risk of a war must also be balanced against the damage to global security from another prolonged and feckless routine of inspections in Iraq. Those who propose such containment rarely acknowledge the previous failure and collapse of that strategy, nor do they explain why it would not be repeated. But history suggests the result would be the survival of a dangerous threat, and a rush by other rogue states to stockpile weapons of mass destruction.

Sen. Levin and other Democrats also point to the difference between U.S. treatment of Iraq and North Korea. As Minority Leader Thomas A. Daschle put it recently, "North Korea could also be an immediate threat and we're not going to war with North Korea. . . . If we can talk with the Koreans to try to reduce the level of threat, why is it that we can't talk with the Iraqis?" Why not sit down and negotiate with Saddam Hussein? For the simple reason that -- thankfully -- the U.S. position in the Persian Gulf is not as weak as it is in Northeast Asia. The Bush administration has been pushed toward an unsatisfactory combination of containment and dialogue with dictator Kim Jong Il because military action would likely result in the devastation of an ally, South Korea. In contrast, almost all military experts believe Iraq's armed forces can be defeated without such costs -- and military intervention has been justified by Iraq's repeated violation of U.N. resolutions. It may not be possible to disarm North Korea anytime soon -- but does that mean Iraq should not be disarmed?

The critics' ultimate argument is about timing and urgency. Yes, Saddam Hussein must be disarmed, they concede, but why now? "I don't think he's an imminent threat to us," said Sen. Levin. That conclusion implicitly rejects the considerable evidence that terrorists planning attacks with chemical and biological weapons are now based in Iraq, and assumes that Saddam Hussein would never supply them with anthrax, VX nerve agent or other weapons. Yet, even taking that chance -- which strikes us as unwise -- the issue of Saddam Hussein's continuing defiance of the United Nations would remain. The Iraqi dictator was granted a cease-fire 12 years ago on condition that he disarm; he did not do so, despite repeated orders from the Security Council. Last November he was given a "final opportunity," which he also rejected. In any such standoff, a moment finally arrives when those who would preserve global order must act, or abandon that order. This is that moment.