On October 7, the British edition of the Financial Times led its front page with the headline: "War to oust Saddam `illegal.' " The British government's chief legal officers, the story explained, had advised Prime Minister Tony Blair that military action against Iraq not authorized by the United Nations Security Council would violate the U.N. charter. Blair wants to back President Bush, but he has promised Parliament that Britain "will always act in accordance with international law." It was a foolish promise.

Whether unauthorized military action against Iraq would, in fact, violate international law is debatable, as Stuart Taylor explained with customary lucidity in his column in National Journal last week. Article 2 of the charter forbids "the threat or use of force against the territorial integrity or political independence of any state" without Security Council approval. The only exception, in Article 51, is the right of self-defense in the event of armed attack. On the face of it, then, pre-emptive action of the kind America is threatening against Iraq is illegal.

One can argue, however, that Article 2 has been flouted so widely and so often, including in ways that few now actually regret, that it no longer has force. The blockade of Cuba in 1962, Israel's raid against Iraq's nuclear facilities in 1981, the bombing of Serbia in 1999, were all illegal. That did not make them wrong, as even many of today's doves would admit. Yet this is surely an unsatisfactory conclusion if you want to maintain, as many do, that the administration should "respect international law." One would not call on American citizens to respect the laws of the United States insofar as they agreed with them. Respecting only those laws that suit you is not respect for the law.

Many Americans who are uncomfortable with the aggressive unilateralist tendencies of the administration-with the war-mongering of Vice President Cheney and Defense Secretary Donald Rumsfeld, in particular-were pleased when President Bush sought U.N. action in his speech of September 12: "A welcome departure from the ostentatious machismo of the hard-line hawks and his own past lurches into unilateralism," Taylor called it in the same column. It was the right move, but not for that reason. The effort to command support at the United Nations may yet fail-but if it succeeds, it will only be because "ostentatious machismo" made the threat of unilateral action credible. If Secretary of State Colin L. Powell were the administration's sole voice on foreign policy, then the prospects of the U.N.'s sanctioning action, or of Iraq's agreeing to disarm under threat of attack, would be nil.

Bush was nonetheless right to challenge the U.N. to deal with Iraq. And he was right to explain at length why Saddam Hussein is a menace, and not just to his region or the United States. America's course will be easier militarily and politically if the administration justifies its position coherently. If it gains wide international support for its plans, up to and including authority from the Security Council for military action, so much the better. But there is a danger in calling for cooperation in terms that invoke the authority of international law-given that America is willing, rightly, to contravene that law in the end and go it alone.

The problem is that this duality looks like bad faith. Outside America, Bush is heard as saying that international law is fine when it helps the United States get what it wants, but is instantly disposable otherwise. International law must be made to constrain Iraq, says the administration, but not America, which presumably stands above it. However politely Bush addresses the U.N. General Assembly, such thinking does not express respect for international law. It looks like a sham that will be dropped the moment it becomes inconvenient.

In the eyes of many European critics, such a posture is worse than unilateralism: It is unilateralism plus hypocrisy. If the diplomatic goal is to win support and build an alliance, invoking international law while promising to break it if necessary is not the best course.

Popular opinion in Europe wants America not just to take its case to the U.N.-it wants America to obey the U.N.'s ruling. Blair's legal advisers are apparently in tune with that thinking. And the European majority may be correct: Respect for international law probably does imply what Europeans say it implies. That is why respect for international law should not figure very prominently either in the administration's judgments about what is right, or in the demands it makes on Europe and the rest of the world for support. Instead, the thing to emphasize in seeking allies is mutual interest-a stronger and more honest basis for cooperation.

I see why many find this depressing. The hope that international relations might one day be regulated by lawful authority, and not by force and self-interest, is centuries old. It is a fine ideal. Like other countries, and despite its unprecedented superiority in military power, the United States would have an enormous interest in the creation of a lawful world order, even if the result were to limit its own freedom of action. On this, the doves who emphasize the primacy of the U.N. and international law, and who deplore American unilateralism as a failure of vision, have a point. But then they get two big things wrong.

The first mistake, a view popular in Europe, is to regard American hegemony as an order based on might and nothing else. It is as though Pax Americana were not much different morally from Pax Romana, or from the order that would have prevailed if the Axis powers had won the Second World War, or if the West had lost the Cold War. In each case, might is right. End of discussion.

But if the world is to choose between an order based on lawful authority and an order based on force, it matters a lot, doesn't it, to know who controls that force, and how and why it will be used? The United States is a nation of laws, a democracy, an open society, with a government accountable to and closely scrutinized by its citizens. America has struck at an enemy outside its borders in Afghanistan, and is moving now against Iraq, not from motives of conquest or empire-building, but because it was attacked without provocation and is seeking to protect itself. As a European, a citizen of a would-be rival superpower, I cannot feel threatened by America's might. I am glad of it, and am grateful for it. Untrammeled Soviet power, in contrast, always seemed to have drawbacks.

Doves and multilateralists will concede that Pax Americana is a happier outcome than, say, Hitler's Thousand-Year Reich. Yet they still insist that American force, enlightened as it may be, is a far worse basis for global order than the lawful authority of a body like the United Nations. Well, that depends. In the long term, the very long term, they might conceivably be right. The trouble is, before we even get to the medium term, a lot of us might be dead.

A few weeks ago, I chaired a debate in London on the implications of September 11. The speakers were Peter Singer of Princeton University and Jonathan Glover of King's College London, two leading moral philosophers. It turned out there was little debate: They agreed about most things, especially that the U.N. should have a veto over American action against Iraq. The alternative, they told an eagerly appreciative audience, was to settle for the amorality of a world ruled by force. I asked whether September 11 had made any difference to their thinking. The answer, so far as I could tell, was no.

It should have. Even if multilateralists are right about the kind of world order we should aspire to, building it would be at best the work of decades. It is not just a question of strengthening institutions such as the United Nations. The world's governments would have to reform themselves as well so that all of them, not just some of them, were genuine democracies. Otherwise, what moral authority can a consensus among rulers represented at the U.N. really hope to command? And this is to say nothing of designing constitutional machinery to give international law moral authority on a par with domestic law. How long is all this going to take?

Terrorists want to kill us right now, and governments such as Iraq's wish them well. If September 11 changed nothing else, it should have ended complacency about the threat of terrorists who might get hold of weapons of mass destruction. Action on this cannot wait decades for a better system of global governance.

If international law forbids such action, international law is wrong. One day the world should get around to changing it. Just now, other tasks are more pressing.

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