"The danger is clear: using chemical, biological, or, one day, nuclear weapons obtained with the help of Iraq, the terrorists could fulfill their stated ambitions and kill thousands or hundreds of thousands of innocent people in our country or any other..." the president said in a speech calling for military action.

However, in the two months that U.S. troops have searched for weapons, they have found vehicles that may have been used as mobile chemical weapon labs, but they have not located any of the large amounts of dangerous materials Saddam was believed to have possessed.

Secretary of State Colin Powell on Monday reiterated the administration's belief that Saddam's government possessed WMD.

"There were weapons of mass destruction in Iraq," he said. "It wasn't a figment of anyone's imagination."

Still, some politicians, even many who supported the war, want to know more about the intelligence-gathering that led to the reports and make sure the threat was not exaggerated to build support for a war that was already planned.

"I think it [hyping of intelligence] happens all the time on the eve of war," said Democratic Sen. Joe Biden of Delaware, who sits on the Senate Foreign Relations Committee.

Divided opinions lead to intelligence investigations

Thus far, three separate investigations into the intelligence reports that established Iraq's weapons capability have been initiated -- two in the U.S. and one in Britain.

The U.S. Central Intelligence Agency (CIA) is conducting an internal review of a top secret intelligence report issued last October that provided President Bush with his last overview of Iraq's weapons program before the war. In addition, the agency is preparing to turn over to Congress the underlying documents that were used to create the top secret report.

Both the House of Representatives and the Senate are planning to conduct their own reviews of prewar intelligence.

CIA director George Tenet denied in a prepared statement issued last week that the internal review meant that the Bush administration had doctored evidence of WMD to support its foreign policy objectives.

"The integrity of our process was maintained throughout, and any suggestion to the contrary is simply wrong," Tenet said.

Tony Blair under fire in Britain

Across the Atlantic Ocean, Blair is facing harsh questioning from his government about the lack of WMD discoveries in Iraq thus far.

Opposition Tory Party and Liberal Democrat members called for an independent investigation and the publication of intelligence that was provided to the British government.

The British all-party Intelligence and Security Committee is already conducting an inquiry into the allegations, but the investigation will take place behind closed doors.

"The whole credibility of his government rests on clearing up these charges," Tory leader Iain Duncan Smith said.

Blair says he is not intimidated by the investigations.

"I stand absolutely, 100 percent behind the evidence, based on intelligence, that we presented people," Blair responded.

Where are the weapons?

Officials are divided on whether weapons will eventually be discovered in Iraq, whether they were destroyed before the war, whether they were transported to another country, or whether Iraq had only limited weapons development capability.

U.S. Defense Secretary Donald Rumsfeld recently admitted that finding the weapons would not be easy.

"I never believed that we'd just tumble over weapons of mass destruction in that country," he said on Fox News Sunday.

David Albright, a former analyst and inspector who monitored Iraq's nuclear program from 1992 to 1997, told the NewsHour that the Bush administration exaggerated Iraq's ability to produce WMD.

"The inspections were working, certainly not finding everything, but were making it very hard for Iraq to maintain any kind of robust weapons of mass destruction program," Albright said.

Former United Nations chief weapons inspector Richard Butler believes that Iraq was in possession of WMD, but said he is not certain that weapons will ever be found.

"Will they find them? I don't know if they will find them," Butler said in April. "The Iraqis could have destroyed them, or hidden them, or moved them across the border, for example, to Syria."

-- By Anne Schleicher, Online NewsHour