President Bush said Tuesday that Iraq undoubtedly posed a threat to America last year and the U.S.-led invasion was justified, despite his outgoing arms inspector's conclusion that Saddam Hussein had no weapons of mass destruction (search).

But Bush and his aides backed away from often-stated predictions that such weapons will eventually be found in Iraq. And the president deflected questions about the discrepancies between his dire warnings on Iraq and former chief inspector David Kay's (search) findings.

"There is no doubt in my mind that Saddam Hussein was a grave and gathering threat to America and the world," Bush said. "And I say that based upon intelligence that I saw prior to the decision to go into Iraq and I say that based upon what I know today. And the world is better off without him."

Kay believes his team's failure to find banned weapons in Iraq points to problems in the intelligence suggesting they were there, and he said over the weekend that the CIA owes Bush an explanation.

While inspectors have been unable to unearth weapons of mass destruction, they have found new evidence that Saddam's regime quietly destroyed some stockpiles of biological and chemical weapons in the mid-1990s, Kay told The Washington Post in an interview posted on the newspaper's Web site Tuesday night.

Kay said the evidence consisted of contemporaneous documents and confirmations from interviews with Iraqis and indicated Saddam did make efforts to disarm well before Bush began making the case for war.

The chairman of the House Intelligence Committee, Rep. Porter Goss, said in an Associated Press interview Tuesday that Kay was doing a favor for the nation's intelligence system with his harsh criticism of the CIA's flawed prewar estimates.

Goss blamed the problem on underestimation of the fear and repression in Saddam's Iraq and insufficient intelligence budgets during the 1990s. He said the intelligence system needs more resources.

"I already knew it, but I know it in a more reinforced way now, and I figure Dr. Kay has done me a favor," Goss said.

Bush, during a meeting with Polish President Aleksander Kwasniewski (search), said he had "great confidence in our intelligence community," and he displayed no interest in such an accounting from the CIA.

The president said he wanted to let American weapons inspectors complete their search in Iraq before drawing conclusions. That work is 85 percent complete, Kay has said.

Last year, the president made Iraq's alleged weapons cache a central rationale for the Iraq invasion.

On Jan. 22, 2003, Bush told an audience in St. Louis, "The dictator of Iraq has got weapons of mass destruction." On the eve of the war in March, he said, "Intelligence gathered by this and other governments leaves no doubt that the Iraq regime continues to possess and conceal some of the most lethal weapons ever devised."

Sunday, after nine months of searching, Kay said, "I don't think they exist." Kay quit his post on Friday.

Bush cited other reasons Tuesday behind his decision to go to war, and he tried to direct Americans' attention to the future of Iraq, not his own past assertions.

"America is more secure, the world is safer, and the people of Iraq are free," Bush said.

"We're now at the business of making sure Iraq is free and democratic," Bush said. "That's important, as well, for long-term stability and peace in the world, and we're making good progress toward that goal."

Bush did not mention twin roadside bombings west of Baghdad that killed three American soldiers Tuesday.

The Polish leader offered his own defense of Bush, saying many experts believed before the war that Iraq had built banned weapons. Kwasniewski said a top U.N. weapons inspector had told him several months before the invasion that "Saddam has these weapons or is ready to produce these weapons."

Senate minority leader Tom Daschle, D-S.D., demanded a new investigation by an independent commission, or a broadened probe by the Senate Intelligence Committee, into the "administration's role in the intelligence failures leading up to the war with Iraq." The Republican-controlled Senate Intelligence Committee is currently looking into what the CIA knew before the war, but the scope doesn't include the Bush administration's role.

Bush ignored a reporter's question about whether he would support or resist a new probe.

Daschle's request for a new inquiry led to a testy exchange in the Cabinet Room on Tuesday afternoon. Bush met with congressional leaders of both parties, and Daschle told him it was important to get to the bottom of whether intelligence was misused.

Bush denied his administration had manipulated intelligence to bolster the case for war, and told lawmakers Kay's search had been worthwhile, according to a participant in the meeting. Bush said he had not given up on the weapons hunt.

Daschle replied that it is crucial such an apparent intelligence failure does not happen again, noting that many lawmakers had based their votes on authorizing force on the intelligence.

Democratic presidential contenders grabbed hold of Kay's conclusion on the absence of banned weapons as they made 11th-hour appeals to New Hampshire voters.

"The administration did cook the books," Howard Dean told reporters. "I think that's pretty serious."

Bush broke a pledge to go to war "legitimately, as a last resort," Sen. John Kerry of Massachusetts said on ABC's "Good Morning America."

American voters "want a foreign policy that's based on truth and that actually makes America stronger, doesn't put it at greater risk," Kerry said.