It was the fifth speech in less than three weeks, where the president laid out his plan for victory in Iraq, reports CBS News senior White House correspondent Bill Plante.
"I know that some of my decisions have led to terrible loss — and not one of those decisions has been taken lightly," Mr. Bush declared in a televised speech to the nation Sunday, his first from the Oval Office since announcing the invasion of Iraq in March 2003.
"It was probably the best speech he's ever given on Iraq because it was so realistic. This was one speech on Iraq not delivered from Mount Disneyland," University of Virginia political analyst Larry Sabato told CBS Radio News.
"He admitted that the past to the present has been strewn with mistakes and misjudgments, by him and by his key people. That's very significant," Sabato said.
"I think that was a very important thing for him to do. He's been a little bit more humble these days," said CBS News correspondent Gloria Borger.
At a, Mr. Bush also acknowledged that a prewar failure of American intelligence — claiming that Saddam Hussein possessed weapons of mass destruction — has complicated the United States' ability to confront other potential emerging threats such as Iran.
"Where it is going to be most difficult to make the case is in the public arena," Mr. Bush said. "People will say, if we're trying to make the case on Iran, 'Well, if the intelligence failed in Iraq, therefore, how can we trust the intelligence on Iran?'"
The president held out the promise Sunday night that when the Iraqi military gains strength and self-government moves forward, "it should require fewer American troops to accomplish our mission. I will make decisions on troop levels based on the progress we see."
The language was not specific enough for President Bush's critics.
"While I appreciate the president's increased candor, too much of the substance remains the same and the American people have still not heard what benchmarks we must meet along the way to know that progress is being made" and when the troops "can begin to come home," said Senate Democratic leader Harry Reid of Nevada.
His House counterpart, Rep. Nancy Pelosi, D-Calif., said: "Tonight the president acknowledged more of the mistakes he has made in Iraq, but he still does not get it. Iraq did not present an imminent threat to the security of the United States before he began his war of choice."
The president said that despite setbacks, "Not only can we win the war in Iraq — we are winning the war in Iraq."
There is a difference, he said, between "honest critics who recognize what is wrong, and defeatists who refuse to see that anything is right."
That drew a rebuttal from Sen. Edward M. Kennedy, D-Mass.