Bush Appeals to Nation on Iraq

President Bush appealed to the nation in a prime time address on Iraq Thursday night -- his latest effort to buy time for his Iraq war strategy and shore up support among wavering Republicans and critical Democrats who have become increasingly frustrated with the lack of political progress and stability in Iraq.

The president framed the Iraq conflict as he has in the past, as a key component of a broader war against al Qaeda and Islamic extremists.

"Terrorists and extremists who are at war with us around the world are seeking to topple Iraq's government, dominate the region, and attack us here at home," Bush said in a televised, live address from the Oval Office in the White House.

"If Iraq's young democracy can turn back these enemies, it will mean a more hopeful Middle East and a more secure America ... our moral and strategic imperatives are one: we must help Iraq defeat those who threaten its future and also threaten ours," he said.

'We Can Maintain Our Security Gains With Fewer American Forces'

With a majority of Americans telling pollsters they would like to see American troops leave Iraq, the president said he is ordering some troops home.

Bush said 2,200 Marines are coming home immediately and will not be replaced, and an Army brigade of 3,500 will be out of Iraq by Christmas. These units were already scheduled to come home, but now, they will not be replaced.

"General Petraeus believes we have now reached the point where we can maintain our security gains with fewer American forces," Bush said.

7,000 More Troops in Iraq By Next Summer

Bush's plan is to withdraw five brigades by mid-July -- approximately 23,000 troops, leaving about 137,000 U.S. troops in place by next summer.

While Bush portrayed the redeployment as a troop withdrawal, there will actually be 7,000 more troops in Iraq next summer than there were before Bush deployed additional forces to Iraq in January as part of a troop surge plan to quell sectarian violence.

In his more than 17-minute address, Bush suggested any troop redeployment will be heavily conditioned on stability in Iraq -- far from the rapid withdrawal of troops wanted by Democratic leaders in Congress.

"The principle guiding my decisions on troop levels in Iraq is 'return on success'," Bush said. "The more successful we are, the more American troops can return home. And in all we do, I will ensure that our commanders on the ground have the troops and flexibility they need to defeat the enemy."

The president said after December, the military would be looking to try to hand over more responsibility to Iraqi forces.

"Over time, our troops will shift from leading operations, to partnering with Iraqi forces, and eventually to overwatching those forces," he said.

While the president cited the Iraqi leaders for not meeting benchmarks for political stability, he made clear that Iraq must be stabilized before any real coming together of the Sunni, Shiite and Kurdish factions could happen.

"For Iraqis to bridge sectarian divides, they need to feel safe in their homes and neighborhoods. For lasting reconciliation to take root, Iraqis must feel confident that they do not need sectarian gangs for security," Bush said.

ABC NEWS has learned that in a report to Congress Friday on Iraq's political and security progress, the Bush administration will say nine of the Iraq benchmarks are "satisfactory", seven are unsatisfactory and 2 are mixed.

The report cites 'satisfactory' progress in terms of elections, even though elections have yet to be held and no date has been set.

Iraq Strategy Part of 'Broader Vision' for Middle East

The president explained his Iraq strategy as part of a larger policy in the Middle East.

"If we were to be driven out of Iraq, extremists of all strains would be emboldened. Al Qaeda could gain new recruits and new sanctuaries. Iran would benefit from the chaos and would be encouraged in its efforts to gain nuclear weapons and dominate the region," Bush said.

"Extremists could control a key part of the global energy supply. Iraq could face a humanitarian nightmare. Democracy movements would be violently reversed. We would leave our children to face a far more dangerous world. And as we saw on September the 11th, 2001, those dangers can reach our cities and kill our people," he said.

During a lunch with network anchors attended by ABC News' Charles Gibson and George Stephanopoulos Thursday afternoon, Bush explained that the Iraqi government has said they want U.S. troops in Iraq on a long-term basis.

Bush made clear that the U.S. will have an enduring presence in Iraq, that will go beyond his presidency, but he does not necessarily envision permanent U.S. bases in that country.

Bush's Eighth Appeal to Nation on Iraq

The president's address comes after a week of testimony on Capitol Hill by Army Gen. David Petraeus, the top U.S. military official in Iraq and Ambassador to Iraq Ryan Crocker, the top diplomat -- telling lawmakers that the troop surge strategy in the United States has had uneven success.

It's Bush's eighth prime time address on Iraq since the invasion of Iraq in March 2003.

The president faced an American public increasingly skeptical about the war that the four-year-old conflict is making the country safer -- something the top U.S. military general in Iraq had trouble doing on Capitol Hill this week when he said he didn't know whether the Iraq War strategy would make America any safer.

The president must also shore up support among Republican senators who have voiced frustration with the lack of progress in Iraq.

Democrats in Congress lack the 60 votes necessary in the Senate to force the president to withdraw U.S. forces from Iraq. The Senate majority leader is attempting to woo those Republicans to force the president to fundamentally change course.

Democratic Rebuttal to Bush Address

Democrats responded to the president's address by arguing his latest strategy is a continuation of a flawed policy in Iraq that is making the nation less secure.

"The President's Iraq policies have worsened America's security. Hundreds of billions have been spent. Our military is strained. Over 27,000 Americans have been wounded, and over 3,700 of our best and brightest have been killed," Democratic Senator Jack Reed of Rhode Island said in a nationally televised rebuttal.

"Tonight, a nation eager for change in Iraq heard the President speak about his plans for the future. But once again, the President failed to provide either a plan to successfully end the war or a convincing rationale to continue it," Reed said.

Among the clamor to assail Bush, one of the candidates running to replace Bush has found a unique way to be heard.

Democratic presidential candidate, former Sen. John Edwards, D-N.C., bought two minutes of air time on MSNBC, that aired after Bush's televised address from the White House.

"Unfortunately, the president is pressing on with the only strategy he's ever had more time, more troops, and more war," Edwards says in the ad.

Edwards has been pushing Congress including his 2008 rivals Sens. Hillary Clinton and Barack Obama, to vote against legislation that would further fund the war without a withdrawal date.

Is the Iraq War Making the U.S. Any Safer?

One of the Republicans who is increasing skeptical of the Iraq War strategy is outgoing Sen. John Warner of Virginia, who is retiring after 2008. While he has criticized the president's policy, he has never supported a Democratic withdrawal plan.

"Are you able to say at this time if we continue what you've laid before the Congress here as a strategy, do you feel that is making America safer?" Warner asked Petraeus during a charged session of the Armed Services Committee Tuesday.

"Sir, I believe that this is indeed the best course of action to achieve our objectives in Iraq," Petraeus answered.

Does that make America safer?" Warner pressed.

"Sir, I don't know, actually," the general said. "What I have focused on and riveted on is how to accomplish the mission of the multinational force in Iraq."

Tribal Leader Cooperating With U.S. Murdered

The president's speech came on a day when the administration was dealt a major blow to its effort to persuade local tribal leaders in Iraq to cooperate with the U.S. against al Qaeda in Iraq.

A Sunni tribal leader, Sheik Abdul Sattar, cooperating with the United States against al Qaeda in Iraq, was killed in an improvised explosive device attack near his house in Anbar Province.

The leader was the latest and most prominent tribal leader to be targeted precisely because of his close association with the United States.

A senior White House official suggested the killing was a blow, saying: "The sheik's death couldn't be worse timing for the Bush administration. And we can't help but be worried."

ABC News' Charles Gibson, George Stephanopoulos, Jonathan Karl, Ann Compton, Luis Martinez and Jennifer Duck contributed to this report.