The buildup puts Bush on a collision course with the new Democratic Congress and pushes the American troop presence in Iraq toward its highest level. It also runs counter to widespread anti-war passions among Americans and the advice of some top generals.
In a prime-time address to the nation, Bush pushed back against the Democrats' calls to end the unpopular war. He said that "to step back now would force a collapse of the Iraqi government, tear that country apart and result in mass killings on an unimaginable scale."
Under Mr. Bush's plan, Baghdad will be divided into nine districts, and a battalion of American combat troops – about 800 soldiers – will be sent into each one to operate with Iraqi forces, clearing out insurgents and death squads, reports CBS News national security correspondent David Martin. Unlike previous operations, the American troops will stay in the neighborhoods until reconstruction teams can restore water and electricity and put unemployed Iraqis back to work.
Pentagon officials expect U.S. troops to stay in the streets for about six months before they turn security over to the Iraqis, Martin reports. If it hasn't happened in six months, one official said that we'll know the plan isn't working.
In addition to extra U.S. forces, the plan envisions Iraq's committing 10,000 to 12,000 more troops to secure Baghdad's neighborhoods — and taking the lead in military operations.
Even before Mr. Bush's address, theof Congress renewed their opposition to a buildup. "This is the third time we are going down this path. Two times this has not worked," House Speaker Nancy Pelosi said after meeting with the president prior to the speech. "Why are they doing this now? That question remains."
There was criticism from Republicans, as well. "This is a dangerously wrongheaded strategy that will drive America deeper into an unwinnable swamp at a great cost," said Sen. Chuck Hagel, a Vietnam veteran and potential Republican presidential candidate.
Senate and House Democrats are arranging votes urging the president not to send more troops. While lacking the force of law, the measures would compel Republicans to go on record as either bucking the president or supporting an escalation.
The president faces a tough and skeptical audience: According to, just 23 percent approve of his handling of the war, while 72 percent disapprove.
Usually loath to admit error, Bush said it also was a mistake to have allowed American forces to be restricted by the Iraqi government, which tried to prevent U.S. military operations against fighters controlled by the radical Shiite cleric Muqtada al-Sadr, a powerful political ally of Prime Minister Nouri al-Maliki. The president said al-Maliki had assured him that from now on, "political or sectarian interference will not be tolerated."
After nearly four years of bloody combat, the speech was perhaps Bush's last credible chance to try to present a winning strategy in Iraq and persuade Americans to change their minds about the unpopular war, which has cost the lives of more than 3,000 members of the U.S. military and many thousands of Iraqis as well as more than $400 billion.
"He has really put it all on the line tonight," said CBS News chief Washington correspondent Bob Schieffer. "The question you have to ask is, 'If this doesn't work, where does the president go from here?'"
Bush's approach amounts to a huge gamble on al-Maliki's willingness — and ability — to deliver on promises he has consistently failed to keep: to disband Shiite militias, pursue national reconciliation and make good on commitments for Iraqi forces to handle security operations in Baghdad.
"Our past efforts to secure Baghdad failed for two principal reasons: There were not enough Iraqi and American troops to secure neighborhoods that had been cleared of terrorists and insurgents," the president said. "And there were too many restrictions on the troops we did have."
He said American commanders have reviewed the Iraqi plan "to ensure that it addressed these mistakes."
With Americans overwhelmingly unhappy with his Iraq strategy, Bush said it was a legitimate question to ask why this strategy to secure Baghdad will succeed where other operations failed. "This time we will have the force levels we need to hold the areas that have been cleared," the president said.
While Bush put the onus on the Iraqis to meet their responsibilities and commit more troops, he did not threaten specific consequences if they do not. Iraq has missed previous self-imposed timetables for taking over security responsibilities.
Bush, however, cited the government's latest optimistic estimate. "To establish its authority, the Iraqi government plans to take responsibility for security in all of Iraq's provinces by November," the president said.
Still, Bush said that "America's commitment is not open-ended. If the Iraqi government does not follow through on its promises, it will lose the support of the American people and it will lose the support of the Iraqi people. Now is the time to at."
Resisting calls for troop reductions, Bush said that "failure in Iraq would be a disaster for the United States. ... A democratic Iraq will not be perfect. But it will be a country that fights terrorists instead of harboring them."
But Bush warned that the strategy would, in a short term he did not define, bring more violence rather than less.
"Even if our new strategy works exactly as planned, deadly acts of violence will continue, and we must expect more Iraqi and American casualties," he said. "The question is whether our new strategy will bring us closer to success. I believe that it will."
Bush's warning was echoed by Sen. John McCain, a Republican and a leading proponent of a troop increase. "Is it going to be a strain on the military? Absolutely. Casualties are going to go up," the senator said.
Bush said he considered calls from Democrats and some Republicans to pull back American forces. He concluded it would devastate Iraq and "result in our troops being forced to stay even longer."
But he offered a concession to Congress — the establishment of a bipartisan working group to formalize regular consultations on Iraq. He said he was open to future exchanges and better ideas.
The latest increase calls for sending 17,500 U.S. combat troops to Baghdad. The first of five brigades will arrive by next Monday. The next would arrive by Feb. 15 and the reminder would come in 30-day increments.
Bush also committed 4,000 more Marines to Anbar Province, a base of the Sunni insurgency and foreign al Qaeda fighters.