President Obama tonight delivered his second nationally-televised Oval Office address to herald the end of U.S. military combat operations in Iraq and to remind the American people of his pledge to bring the war to a close.
"Operation Iraqi Freedom is over," the president said. "The Iraqi people now have lead responsibility for the security of their country. This was my pledge to the American people as a candidate for this office."
Mr. Obama's address, seven and a half years after President George W. Bush launched a U.S.-led invasion of Iraq, cast the milestone as a sign that America can prevail in the face of stiff economic challenges at home and fierce fighting abroad in Afghanstan.
"This milestone should serve as a reminder to all Americans that the future is ours to shape if we move forward with confidence and commitment," Obama said.
The president praised America's men and women in uniform for shifting the tide in Iraq, saying he has been "awed" by their sacrifice and "courage and resolve."
More than 4,400 U.S. military service members have died in Iraq. At its peak in 2007, more than 170,000 troops were in the country; only around 50,000 troops remain. The war has cost taxpayers an estimated $885 million.
"The United States has paid a huge price to put the future of Iraq in the hands of its people," Obama said. "We have persevered because of a belief we share with the Iraqi people -- a belief that out of the ashes of war, a new beginning could be born in this cradle of civilization. Through this remarkable chapter in the history of the United States and Iraq, we have met our responsibility. Now, it is time to turn the page."
Today the official name of the military mission in Iraq changes to "Operation New Dawn," but the president cautioned that does not mean the violence in Iraq is over, nor is the U.S. commitment to help fight it.
"Extremists will continue to set off bombs, attack Iraqi civilians and try to spark sectarian strife," Obama said.
"Tonight, I encourage Iraq's leaders to move forward with a sense of urgency to form an inclusive government that is just, representative and accountable to the Iraqi people. And when that government is in place, there should be no doubt: the Iraqi people will have a strong partner in the United States.
"Our combat mission is ending," he said, "but our commitment to Iraq's future is not."
As military forces draw down, a corps of U.S. civilians led by the U.S. State Department will support the fledgling government and help strengthen civil society.
All American forces are scheduled to leave Iraq by the end of 2011 under an agreement between the U.S. and Iraqi governments, but experts say those terms will likely be renegotiated due to the persistent challenges Iraq faces.
Civilian violence has declined since its peak in September 2006, but at least 270 Iraqis were killed in attacks just this month. And six months after Iraq held its latest , a governing coalition remains unformed with little sign the stalemate will end soon.
Republicans today criticized the president's handling of the milestone, chiding him for taking credit for a moment they say was largely made possible because of policies and strategies implemented by President George W. Bush.
"By adopting the Bush administration's plan for winding down the war and transitioning security responsibilities to the Iraqi military over time, the President has enabled us and the Iraqis to build on the gains our troops have made," said Senate Minority Leader Mitch McConnell.
And several Republicans today pointed out that as a senator Obama had openly opposed Bush's 2007 troop surge strategy, which is now largely seen as having been effective.
"Some leaders who opposed, criticized, and fought tooth-and-nail to stop the surge strategy now proudly claim credit for the results," said House Minority Leader John Boehner. "Today we mark not the defeat those voices anticipated – but progress."
Obama tonight acknowledged the debate over the Iraq war and said he called former President Bush today to discuss the milestone.
"It's well known that [Bush] and I disagreed about the war from its outset. Yet no one could doubt President Bush's support for our troops, or his love of country and commitment to our security," Obama said. "As I have said, there were patriots who supported this war, and patriots who opposed it. And all of us are united in appreciation for our servicemen and women, and our hope for Iraq's future."
The president also used the moment to reiterate his commitment for the strategy in Afghanistan, where thousands of additional U.S. troops have been arriving to battle the Taliban and al Qaeda strongholds.
But he used the model of Iraq to insist that the U.S. will "begin a transition to Afghan responsibility" in July 2011. "Make no mistake," the president said, "this transition will begin - because open-ended war serves neither our interests nor the Afghan people's."
In seeking to "turn the page" on Iraq, Obama also cast attention on what he described as the nation's most pressing challenge: putting millions of Americans back to work at home to "restore our economy."
"This will be difficult," Obama said, "but in the days to come, it must be our central mission as a people, and my central responsibility as President."
Obama's address capped two days of public events marking the milestone. The president met earlier Tuesday with troops and their families at Ft. Bliss in El Paso, Texas. On Monday, he made his second trip to the Army's Walter Reed Medical Center to meet with wounded veterans.
ABC News' Luis Martinez, Kirit Radia and Sunlen Miller contributed to this report.