(CBS/AP) Gen. David Petraeus told Congress on Monday he envisions the withdrawal of roughly 30,000 U.S. combat troops from Iraq by next summer.
In long-awaited testimony, the commanding general of the war said last winter's buildup in U.S. troops had met its military objectives "in large measure."
As a result, he told a congressional hearing and a nationwide television audience, "I believe that we will be able to reduce our forces to the pre-surge level ... by next summer without jeopardizing the security gains we have fought so hard to achieve."
Testifying in a military uniform bearing four general's stars and a chestful of medals, Petraeus said he had already provided his views to the military chain of command.
Rebutting charges that he was merely doing the White House's bidding, he said firmly, "I wrote this testimony myself. It has not been cleared by nor shared with anyone in the Pentagon, the White House or the Congress."
Petraeus said that a unit of about 2,000 Marines will depart Iraq later this month, beginning a drawdown that would be followed in mid-December with the departure of an Army brigade numbering 3,500 to 4,000 soldiers.
After that, another four brigades would be withdrawn by July 2008, he said. That would leave the United States with about 130,000 troops in Iraq, roughly the number last winter when President Bush decided to dispatch additional forces.
Petraeus said a decision about further reductions would be made next March.
Using charts and graphs to illustrate his points, Petraeus conceded that the military gains have been uneven in the months since President Bush ordered an additional 30,000 troops to the war last winter. But he also said that there has been an overall decline in violence and said, "the level of security incidents has declined in eight of the past 12 weeks, with the level of incidents in the past two weeks the lowest since June of 2006."
Petraeus also said the Iraqi military is slowly gaining competence and gradually "taking on more responsibility for their security."
He cited Anbar province as an example of Iraqis turning against terrorists, adding, "We are seeing similar actions in other locations as well.
Petraeus' testimony came at a pivotal moment in the war, with the Democratic-controlled Congress pressing for troop withdrawals and the Bush administration hoping to prevent wholesale Republican defections.
Mr. Bush and his political allies have worked forcefully in recent weeks to shore up Republican support. One organization with ties to the administration has spent millions on television advertisements, and Mr. Bush traveled to Anbar province last week to highlight improved security in the vast western stretches of Iraq.
Mr. Bush also called Iraqi Prime Minister Nouri al-Maliki in the hours before Petraeus spoke, and is expected to deliver a nationwide address on the war in the next few days.
Mr. Bush has urged lawmakers to listen to Petraeus with an open mind, but CBS News correspondent Chip Reid reports many influential Democrats said they already know what he's going to say and have already rejected it.
"The president's policy as well as his surge are not working," Sen. Joe Biden, D-Del., told CBS News. "The policy was to build up the Iraqi army so we could stand down. It's an abject failure."
Petraeus was one of two witnesses -- Ambassador Ryan Crocker was the other -- at a nationally televised hearing punctuated by numerous protests by anti-war demonstrators in the audience.
Over and over, Rep. Ike Skelton, the Missouri Democrat presiding, ordered police to remove the demonstrators. "This is intolerable," he said at one point.
Skelton and fellow lawmakers spoke first, as is customary in Congress, and Petraeus listened to more than 45 minutes of political rhetoric. His testimony was delayed another 10 minutes by a malfunctioning microphone, but when he began to speak, the lawmakers arrayed on the dais across from him listened intently.
A moderate Midwesterner and chairman of the House Armed Services Committee, Skelton welcomed Petraeus with wistful words of praise.
Petraeus is "almost certainly the right man for the job in Iraq, but he's the right person three years too late and 250,000 troops short," Skelton said.
Petraeus and Crocker listened quietly at the witness table as Skelton called on them to "tell us why we should continue sending our young men and women to fight and die if the Iraqis won't make the tough sacrifices leading to reconciliation."
".... Are we merely beating a dead horse?" the congressman asked.
Rep. Duncan Hunter of California was the first Republican to speak, and he criticized unnamed Democrats for having criticized Petraeus in advance of the nationally televised hearing.
He said the military gains in recent months had produced gains by Iraqis, including an army that is "beginning to emerge as a professional force."
A CBS News/New York Times poll released Sunday found a growing number of Americans said the troop buildup was having a positive impact in Iraq. Thirty-five percent said the surge has made things better, up from 29 percent last month and 19 percent in July. Only 12 percent said it has made things worse, but nearly half said it has had no impact in either direction.
But a separate poll released Monday shows that an overwhelming number of Iraqis say the U.S. troop buildup has worsened security and the prospects for economic and political progress in their country.
Forty-seven percent of those surveyed in a poll conducted by ABC News, Britain's BBC, and Japan's public broadcaster NHK said they want American forces and their coalition allies to leave the country immediately. This was 12 percent more people than harbored those views in a March poll, just as the troop increase was beginning. And 57 percent, including nearly all Sunnis and half of Shiites, said they consider attacks on coalition forces acceptable, a slight increase over the past half year.