WASHINGTON - On the eve of a showdown over Iraq at the United Nations, President Bush once again attempted to link the crisis over Saddam Hussein with the Sept. 11 terrorist attacks and said he had concluded that the risks of inaction clearly outweigh the risks of going to war.

In a 50-minute press conference Thursday night, Bush gave a clear impression that he had made up his mind that the showdown with Saddam and his regime's pace of disarmament was near a climax and that he was ready to commit American forces to war if need be.

While the use of force was a ``last choice,'' Bush said, he also constantly referred to a cost-benefit equation that he had already worked out that hinted at a resolution within days.

On several occasions, Bush talked about Saddam - and the diplomatic efforts to get the Iraqi leader to comply with a United Nations disarmament resolution - in the past tense.

``The price of the attacks on America, the cost of the attacks on America on September 11 were enormous; they were significant,'' Bush said. ``And I am not willing to take that chance again.''

Asked about building anti-war sentiment here and abroad, Bush declared: ``I recognize there are people who don't like war. I don't like war. I wish Saddam Hussein had listened to the demands of the world and disarmed. And that was my hope. That is why I first went to the United Nations to begin with.''

Bush's press conference - his first in prime time since a month after the Sept. 11 attacks - came the day before U.N. chief weapons inspector Hans Blix was supposed to deliver another status report on Iraq's compliance.

Throughout, Bush came back to three central themes, all aimed at aspects of the confrontation that have stymied U.S. attempts to get an international coalition similar to the one that drove Saddam out of Kuwait 12 years ago:

- Bush said Sept. 11 had shown that the risks to the United States had grown with the power -and potential portability - of weapons of mass destruction. Bush, at times, also referred to them as ``weapons of mass terror.'' Skeptics have said Bush has not demonstrated that Saddam poses a clear and present danger.

- He said the United States would do everything to avert the deaths of innocent civilians. The United States, he said, has stockpiled food and medicine to deal with the aftermath of war. Here, too, Bush said the costs of conflict outweigh the perils of allowing Saddam to remain in power. Prominent critics have questioned the impact on average Iraqis, and the costs of occupying Iraq after a war.

But Bush said freedom and stability in the Middle East are immeasurable.
- He said he had tried to work through the United Nations and still held out hope for a new resolution to confront Saddam, but said the United States was clearly not tethered to the Security Council's final decision.

``When it comes to our security, we really don't need anybody's permission,'' Bush said.
Such comments are likely to fuel criticism that the United States is acting arrogantly and unilaterally in the face of world opinion. But Bush said that if war occurs, the United States would have allies at its side - a reference to Britain, Spain and other nations.

Bush's press conference was part of a multipronged administration offensive Thursday that included a ``defending America'' town meeting at the Pentagon by Defense Secretary Donald Rumsfeld, and a Capitol Hill appearance defending the U.S. position on Iraq by Secretary of State Colin Powell.

Besides setting the U.S. on a likely war course in Iraq, there are increasing signs of an intensified hunt for Osama bin Laden and other al-Qaida terrorists. Domestically, the stock market has languished in anticipation of war with Iraq. Consumer confidence - which had rebounded early last year after the terror attacks - has fallen over immediate fears of consequences.

More ominously for Bush, public opinion about a war with Iraq has fractured and hardened around the globe. While a majority of Americans in the latest Gallup Poll still support removing Saddam, anti-war demonstrations have increased at home and abroad. Thousands of high school and college students this week staged walkouts in protest of a war.