Vice President Dick Cheney defended the Bush administration's Iraq policy on Monday, dismissing one House Democrat's recent demand to withdraw troops as a "dangerous illusion."

Cheney labeled "dishonest and reprehensible" those Democrats who voted in October 2002 authorizing President Bush's request to go to war in Iraq and now oppose the effort under the claim that that the president lied to the American people about pre-war intelligence.

"The flaws in the intelligence are plain enough in hindsight. But any suggestion that pre-war information was distorted, hyped or fabricated by the leader of the nation is utterly false," Cheney said in a speech to the American Enterprise Institute, a Washington, D.C.-based think tank.

Cheney praised Rep. John Murtha as a decorated war veteran and "good man, a Marine, a patriot," but called the Democrat's demand last week to withdraw troops illegitimate.

"I disagree with Jack and believe his proposal would not serve the best interest of this nation," Cheney said. "As the prime target of terrorists who have shown an ability to hit America and who wish to do so in spectacular fashion, we have a responsibility to do everything we can to keep terrible weapons out of the hands of these enemies."

Murtha, who voted to give Bush authority to use force against Saddam Hussein in 2002, said in a speech last week that in recent months he has grown increasingly troubled with the direction of the war and with the administration's handling of it.

The recipient of a Bronze Star and two Purple Hearts, Murtha, D-Pa., retired from the Marine Corps reserves as a colonel in 1990 after 37 years in service. The 31-year lawmaker has long held key positions dealing with military issues as the top Democrat on the House Appropriations defense subcommittee. He has demanded that about 160,000 U.S. forces in Iraq be brought back home over six months in a withdrawal proposal.

On Monday, Murtha defended his call to get out of Iraq, saying he was reflecting Americans' sentiment.

"The public turned against this war before I said it," Murtha said, speaking in his hometown of Johnstown, Pa. "The public is emotionally tied into finding a solution to this thing, and that's what I hope this administration is going to find out."

Administration officials have quieted down their criticism of Murtha since White House spokesman Scott McClellan last week compared him to far-left filmmaker Michael Moore. Bush recently praised Murtha during his Asia trip, but called his proposal to withdraw wrong.

Former Sen. John Breaux, D-La., said Cheney on Monday clearly is taking a different approach against war critics than he has in the past.

“I think you saw a different Dick Cheney today. I think someone had talked to him and said ‘tone down the rhetoric,’” Breaux told FOX News.

Breaux said the argument should be discussing strategies on how to end the war in Iraq.

“We’re not getting anywhere by staying the course,” Breaux said. “They have to make that case better than they have been able to make it so far.”

Frank Fahrenkopf, a former Republican National Committee chairman, said it would be wrong to leave Iraq now.

“We’ve got to stay, finish the job in Iraq,” Fahrenkopf told FOX News. ”The worse message would be to leave at this point in time.”

In a speech Monday at the Council of Foreign Relations, Sen. Joe Biden, D-Del., a potential 2008 presidential candidate, agreed that the United States military should not leave yet, but said the president must change the mission.

"The president has to abandon his grandiose goals. Iraq will not become a model democracy anytime soon. We need to refocus our mission on preserving America's fundamental interests in Iraq. That means ensuring Iraq does not become what it wasn't before the war: a haven for terrorists. And we must do what we can to prevent a full-blown civil war that turns into a regional war," Biden said.

He suggested that the United States set three goals: coming to a political settlement that gives all of Iraq's major groups a stake in keeping the country together; strengthening the Iraq's government ability to deliver basic services and revamp reconstruction; and speeding up the training of Iraqi security forces and transfer control to them.

"I believe if the president follows my plan, levels with the American people, and asks for their support, we can start climbing out of the hole he has dug with most of our interests intact," he said.

But while Biden offered advice to the administration, Senate Minority Leader Harry Reid repeated criticism by Democrats that Bush and Cheney misled the American public in order to go to war in Iraq.

"Rather than giving our troops a plan to move forward in Iraq and changing their failed course, they continue to ignore the facts and lash out at those who raise legitimate questions about how the administration misused intelligence in its rush to war," Reid said. He pointed to several statements by administration officials that he said incorrectly linked Iraq with Al Qaeda and an effort to by uranium in Niger.

Cheney countered that those people who claim to have been misled on the intelligence evaluated the same information and reached the same conclusion as the administration.

"American soldiers and Marines serving in Iraq go out every day into some of the most dangerous and unpredictable conditions. Meanwhile, back in the United States, a few politicians are suggesting these brave Americans were sent into battle for a deliberate falsehood. This is revisionism of the most corrupt and shameless variety," Cheney said.

"Some of the most irresponsible comments have come from politicians who actually voted in favor of authorizing the use of force against Saddam Hussein. These are elected officials who had access to the intelligence materials. They are known to have a high opinion of their own analytical capabilities. .... They concluded, as the president and I had concluded, and as the previous administration had concluded, that Saddam Hussein was a threat," he said.

Cheney's speech, one of several recent public appearances by top administration officials defending the decision to go to war, said if the United States backs down, it will have surrendered.

Ticking off a long list of terrorist attacks on American interests going back more than the two decades before the 2003 U.S.-led invasion of Iraq, Cheney said terrorists can not be allowed to get away with any more attacks.

"It is a dangerous illusion to suppose that another retreat by the civilized world would satisfy the appetite of the terrorists and get them to leave us alone. ... A precipitous withdrawal from Iraq would be a victory for the terrorists, an invitation to further violence against free nations and a terrible blow to the future security of the United States of America," he said.

Even with the insistence that the United States must stay the course, Defense Secretary Donald Rumsfeld told FOX News Sunday that it may be possible to cut down the number of troops in Iraq from about 160,000 to fewer than 100,000 by the end of 2006.

Meanwhile, rumors that Al Qaeda terrorist leader Abu Musab al-Zarqawi may have died in a weekend gunfight were thrown out by White House officials Monday, saying it was "highly unlikely."

The Associated Press contributed to this report.