EDITORIAL THE CASE FOR WAR BUSH SEEKS UNITED NATIONS SUPPORT TO TOPPLE HUSSEIN.

ONE day after commemorating the start of the War on Terror on Sept. 11, 2001, President George W. Bush made the case to the world that the next battle must be fought in Iraq to topple Saddam Hussein.

Speaking before a polite but skeptical audience at the United Nations, Bush argued Thursday that the ``world must move deliberately and decisively to hold Iraq in account,'' lest ``the attacks of Sept. 11 ... be a prelude to far greater horrors.''

He made a compelling case, but the work of persuading other nations is far from done.

There can be little doubt of Bush's main points, namely that Iraq poses the greatest threat to international security, and that Hussein is working hard to add nuclear arms to his already formidable cache of weapons of mass destruction.

Given Hussein's long-standing support for terrorist causes, as well as his many attacks on neighboring countries, the prospect of his obtaining the world's most deadly weapons is truly chilling. And it would be dangerously foolish to assume that this time his intentions are benign.

On 9-11, America learned the hard way about the dangers of looking past a menacing threat.

As Bush made clear in his speech, the United Nations already has the authority to take action. By refusing to cooperate with weapons inspectors, Hussein has repeatedly flouted the terms of Iraq's unconditional cease-fire to the 1991 Gulf War. He is also in clear defiance of multiple U.N. resolutions.

Are those resolutions ``to be honored and enforced,'' Bush asked, ``or cast aside without consequence?''

It's a good question, but it raises another that Bush has so far been unable to answer to the satisfaction of all who ask it: Why now?

Why, after more than a decade of Hussein's defying U.N. resolutions, is it suddenly so important to enforce them? Why should the United States enter into a war on Iraq while its forces are fighting in Afghanistan? Why the administration's sense of urgency?

In part, Bush can't provide a conclusive answer to those questions because there are too many unknowns.

Weapons inspectors haven't set foot in Iraq in nearly four years, and when they were there, they were repeatedly harassed and misled. Hussein may be within a year of obtaining nuclear weapons, maybe more, maybe less.

As Bush observed, ``The first time we may be completely certain he has nuclear weapons is when, God forbid, he uses one.''

That would be an unthinkable way to find out.

There may be no need to oust Hussein now, but there's an unconscionable danger in waiting for evidence that may only arrive too late. The lesson of 9-11 is that the country cannot wait for dangers to announce themselves before taking them on. It's better to put an end to Hussein's regime and its program to develop weapons of mass destruction before, and not after, its completion.

Nonetheless, plunging the nation and the world into a deeper level of war is serious business, and Bush, after keeping largely silent about Iraq for the past year, can't expect immediate support on the basis of one speech.

To assemble the international coalition, congressional approval and popular support necessary to wage a war effectively, he will need to continue to press his case. That means not only delivering speeches, but making public as much information as possible to document the extent and nature of the Iraqi threat.

With his address before the United Nations, Bush has begun to make a credible case for taking the War on Terror to Iraq, but the nation and the world still must hear more.