President Bush last night hailed Thursday's Iraqi elections as a vital step toward stabilizing that nation, but warned that despite the political progress more violence lies ahead as Iraq struggles to establish a democracy amid a raging insurgency.

Speaking in a nationally televised prime-time address, Bush made a direct appeal to war opponents, conveying a more humble tone in saying he understands their arguments but asserting that there is no choice but to forge on. "I have heard your disagreement and I know how deeply it is felt," Bush said. "Yet now there are only two options before our country: victory or defeat."

The speech also included his most forthright statement to date about how often Iraq has confounded his own expectations, from weapons of mass destruction that were not found to the problems of reconstructing a civil society in Iraq. "Much of the intelligence turned out to be wrong. And as your president, I am responsible for the decision to go into Iraq," he said. "Yet it was right to remove Saddam Hussein from power."

The 17-minute address capped an intense campaign in recent weeks by the White House to recast the Iraq debate, at a time when rising public skepticism threatens to overwhelm his presidency. Over the past three weeks, Bush has released a new plan for victory, hosted private White House briefings for skeptical members of Congress and delivered four other speeches laying out a more detailed explanation of his war strategy, 33 months after U.S. forces first invaded.

Despite the U.S. death toll -- which is approaching 2,200 -- and widespread skepticism about the war on Capitol Hill and with citizens across in the country, Bush said the United States is making steady gains in Iraq, and suggested that these will lead to troop reductions in the year ahead.

"Some look at the challenges in Iraq and conclude that the war is lost, and not worth another dime or another day," Bush said. "I don't believe that. Our military commanders don't believe that. Our troops in the field, who bear the burden and make the sacrifice, do not believe that America has lost. And not even the terrorists believe it."

Even as he struck a more deferential tone, Bush sought to put his political adversaries on the defensive, saying that "defeatism may have its partisan uses, but it is not justified by the facts."

He also repeated his warning against a rapid withdrawal from Iraq, saying that "to retreat before victory would be an act of recklessness and dishonor -- and I will not allow it." The carnage from roadside bombs and suicide attacks by insurgents in Iraq does not constitute defeat, he added: "This proves that the war is difficult -- it does not mean that we are losing."

Earlier in the day, Vice President Cheney made an unannounced trip to Iraq, keeping it secret even from Iraq's prime minister, who did not know the vice president would be there until walking into a meeting and finding Cheney waiting for him. Cheney's visit occurred against the backdrop of renewed violence, as more than 30 people died in suicide bombings and other attacks since Saturday night.

Visiting with U.S. troops, Cheney -- who in May said the insurgency in Iraq was in its "last throes" -- said that "remarkable" progress is being made there. "I think we've turned the corner, if you will," he said in response to a question from a Marine corporal. "I think when we look back from 10 years hence, we'll see that the year '05 was in fact a watershed year here in Iraq."

Officials traveling with Cheney called it a coincidence that his first visit to Iraq since the fall of Hussein in April 2003 occurred on the same day as Bush's speech. "It just worked out that way," a senior administration said.

Nonetheless, it is clear that the White House hopes the success of Iraq's parliamentary election, particularly in drawing the country's embittered Sunni minority to the polls, proves to be a turning point in the difficult war. Bush was uncharacteristically contrite in his remarks, as he appealed for continued patience from the American people in coming months.

"I ask all of you listening to carefully consider the stakes of this war -- to realize how far we have come in this difficult, noble and necessary cause," he said.

He also said his visits to wounded soldiers and the families of the fallen soldiers have driven home the ramifications of going to war. "I know that some of my decisions have led to terrible loss," he said. "And not one of those decisions has been taken lightly."

Bush's acknowledgment of the difficulties in Iraq won praise from some Democrats, who still called on him to lay down a more concrete plan for withdrawing troops from the conflict. "The president has reached out and spoken more directly than ever before about how we went to war and why it is important to achieve victory, a goal we all share," said Minority Leader Harry M. Reid (Nev.). "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 that our brave troops can begin to come home."

Sen. John W. Warner (R-Va.), chairman of the Armed Services Committee, praised Bush's speech as a resolute call to victory and also as "a high-water mark in his acknowledgment that mistakes have been made and that he has to accept his share of the blame."

Although Bush said that "our forces in Iraq are on the road to victory," others are not so optimistic. Even before the president's speech, Democrats assailed his handling of Iraq and warned that the country could plunge into civil war if Bush does not force a reconciliation among its main factions.

"We've got to tell them they need to come together politically or we'll have to reconsider our presence in Iraq," Sen. Carl M. Levin (Mich.), ranking Democrat on the Armed Services Committee, said on NBC's "Meet the Press."

"You got to bring in the international community and the regional powers to put pressure on the Sunni parties to compromise," agreed Sen. Joseph R. Biden Jr. (D-Del.), who spoke on CBS's "Face the Nation" after returning from a trip to Iraq last week. "If that doesn't happen, all the king's horses and all the king's men, six months from now, are not going to hold this country together."

Republican Sen. John McCain (Ariz.) agreed that challenges lie ahead, but he also praised Bush for being more open with the American people. "Errors have been made," he said on ABC's "This Week." "I think his speeches -- the last four speeches that he has given -- were really good, very appropriate, laid out exactly the situation, certainly as I see it, admission of error, but certainly hope for the future of this process succeeding."

Republicans believe that by focusing on Iraq, Bush has reduced the political damage and has reshaped the debate. A new Associated Press-Ipsos poll found that 57 percent of Americans think U.S. forces should remain in Iraq until the country is stabilized, compared with 36 percent who support an immediate withdrawal. Still, more Americans consider the invasion a mistake than those who believe it was the right decision.

Bush's approval ratings, meanwhile, which reached new lows in recent weeks amid renewed questions about the run-up to the war, are showing signs of rebounding.

The prime-time speech has become a favorite vehicle for the Bush White House to make its case to the American people. Presidents have typically reserved such speeches for times of war or urgent crisis, but Bush has used the format in the past year to promote his Social Security plan, to introduce a Supreme Court nominee and to promise to rebuild the Gulf Coast after Hurricane Katrina. He also has used it to urge the nation to stay the course in Iraq.

During his speech, Bush acknowledged that the war has been thornier than the administration projected. "The work has been especially difficult in Iraq -- more difficult than we expected," Bush said. "Reconstruction efforts and the training of Iraqi security forces started more slowly than we hoped. We continue to see violence and suffering."

Despite the problems, Cheney, speaking in an interview scheduled to air tonight on ABC's "Nightline," refused to back off of his assertion made before the war that the United States would be greeted as liberators by the Iraqi people.

"I don't think I got it wrong," Cheney said. " I think the vast majority of the Iraqi people are grateful for what the United States did. I think they believe overwhelmingly that they're better off today than they were when Saddam Hussein ruled."

President Bush said in his nationally televised speech about the war in Iraq that "our troops in the field, who bear the burden and make the sacrifice, do not believe that America has lost. And not even the terrorists believe it."