President Bush acknowledged yesterday that the multibillion-dollar reconstruction of Iraq has "been uneven" and hobbled by corruption, misplaced priorities and insurgent attacks, but maintained that "quiet, steady progress" would ultimately transform the country.

In an unusually stark assessment of the situation in Iraq, Bush described several strategic errors in managing a rebuilding effort that he said proceeded in "fits and starts." By learning from its mistakes, Bush said, the administration has reshaped its approach and he held out two key cities as models of success to be replicated across Iraq.

"Reconstruction has not always gone as well as we had hoped, primarily because of the security challenges on the ground," Bush said in a speech to foreign policy veterans. "Rebuilding a nation devastated by a dictator is a large undertaking. It's even harder when terrorists are trying to blow up that which the Iraqis are trying to build. The terrorists and Saddamists have been able to slow progress, but they haven't been able to stop it."

The address, the second of four in the days leading up to the Iraqi parliamentary elections Dec . 15, continued an effort to reach out to an increasingly disillusioned public with a more detailed and less triumphal portrait of the advances and setbacks on the ground. While still projecting confidence about the prospects for victory in Iraq, the speech included striking concessions for a president who has repeatedly avoided admitting mistakes out of the conviction that it signals weakness.

"That kind of direct leveling with the country will buy him and the administration some time and space," said Richard N. Haass, a former Bush State Department official who has been critical of the administration's foreign policy. "It's realistic. It's not overreaching. This kind of realism will stand him in good stead because it won't create unrealistic expectations."

Some leading Democrats, on the other hand, found it too little, too late. "His comments this morning were more of the same vague generalities that he has invoked in the past, buttressed by positive anecdotes," said House Minority Whip Steny H. Hoyer (D-Md.). "However, anecdotes do not constitute a plan. Nor do they convey the real-world challenges on the ground."

Rep. John P. Murtha (D-Pa.), a hawk who created a stir by calling for U.S. troops to be withdrawn as soon as practical, said the Bush team has never owned up to the reality of the quagmire. "They kept being unrealistic, illusionary about what was going on in Iraq," he told a news conference. Despite U.S. efforts, "we lost the hearts and minds of the people."

At the same time, House Democrats emerged from a caucus without a consensus on an alternative Iraq policy. While Minority Leader Nancy Pelosi (Calif.) endorsed Murtha's proposal last week, other congressional Democrats consider that an unwise and impractical move that would further destabilize Iraq while casting the party as defeatist as next year's midterm elections approach.

Bush took aim at Murtha, Pelosi and Democratic National Committee Chairman Howard Dean in yesterday's speech. "I reject the pessimists in Washington who say we can't win this war," the president said, again refusing to set a timetable for pulling out U.S. troops.

The White House designed the four speeches to address deepening public concerns about the war. Bush launched such an effort this summer, only to drop it amid Hurricane Katrina, the CIA leak case and other issues, but his advisers have grown increasingly anxious about the political costs of the war at home as his poll numbers have plummeted. Bush is scheduled to speak in Philadelphia on Monday and again in Washington next Wednesday before the Iraqis vote Thursday.

After sticking mainly to friendly military settings in recent months, Bush chose a more skeptical audience yesterday in addressing the Council on Foreign Relations, a nonpartisan organization of diplomats, academics and journalists, many of whom oppose his Iraq policy.

The White House was not allowed to hang its usual slogans, such as "Plan for Victory," behind the presidential lectern. At the same time, Bush refused to honor the council tradition of taking questions from the audience, as Vice President Cheney, Defense Secretary Donald H. Rumsfeld and others have done. Haass, the council president, said he decided it was worth making an exception as Bush became only the second sitting president to address the council.

Only a few hundred members showed up for the hastily organized event at a Washington hotel and empty chairs were removed from the back of the ballroom before Bush arrived. The audience interrupted Bush for applause only once during the speech and even then, many, if not most, did not clap. There was polite applause when he finished.

Rand Beers, former Bush White House official who advised Sen. John F. Kerry (D-Mass.), said he would have liked to have asked Bush why he is so resistant to setting even a loose timetable for withdrawal. "I don't understand why that can't be part of the discussion," Beers said.

Bush focused on what he called the "battle after the battle," the U.S. effort to reconstruct Iraq after decades of tyranny, war and international sanctions in one of history's most audacious attempts at nation building.

Congress has approved $20.9 billion for reconstruction in Iraq, of which $17.5 billion has been obligated and just $12 billion spent, according to the State Department. With security diverting a quarter of the money that has been spent, many projects remain incomplete and electricity is still sporadic for many Iraqis. The failure to do more reconstruction has only fueled the insurgency, according to critics, including some former Bush aides.

Without ever using the words "mistake" or "error," Bush said the administration miscalculated by clearing insurgents out of a city and then moving onto another assignment, only to allow enemy forces to retake control.

It also focused on large reconstruction projects "yet we found our approach was not meeting the priorities of the Iraqi people," so it switched to local projects such as sewer lines and city roads. He also said that "corruption is a problem at both the national and local levels" and that "another problem is the infiltration of militia groups into some Iraqi security forces."

But Bush said the administration has "changed and improved" its approach and held out the cities of Najaf and Mosul as models, the first a holy city for Shiites and the second home to a mix of Sunnis, Shiites and Kurds. He said Americans have rebuilt schools, hospitals and police stations, restored water, repaired roads and bridges and, in one case, reopened a soccer stadium "complete with new lights and fresh sod."

"In places like Mosul and Najaf, residents are seeing tangible progress in their lives," he said. "They're gaining a personal stake in a peaceful future and their confidence in Iraq's democracy is growing. The progress of these cities is being replicated across much of Iraq."

President Bush addresses members of the Council on Foreign Relations.

Defense hawk Rep. John P. Murtha (D-Pa.) said the United States "lost the hearts and minds of the people."