By DARLENE SUPERVILLE
Speaking under sunny skies to some 5,000 people in an amphitheater on the hallowed grounds of Arlington National Cemetery, Obama said the graveyard is "more than a final resting place of heroes."
"It is a reflection of America itself," he said, citing racial and religious diversity in the backgrounds of the men and woman who paid the ultimate sacrifice to preserve "the ideals that bind us as one nation."
His appearance is an annual rite for presidents at the cemetery nestled among verdant hills overlooking the Potomac River. It came months after the end of the U.S. combat mission in Afghanistan, where the number of stationed troops has been reduced to about 10,000 from a peak of more than 100,000.
His tribute also took place against a backdrop of the increasingly complex U.S.-led effort to help Iraq defeat the Islamic State extremist group, which has been gaining momentum in recent weeks by capturing Ramadi there and taking Palmyra in neighboring Syria.
Obama made no mention of America's participation with other nations in the effort to stop the Islamic State. His effort there has come under intensifying criticism since the fall of Ramadi with lawmakers calling for a bigger show of American force there, including ground troops.
Vice President Joe Biden spoke Monday with Iraqi Prime Minister Haider al-Abadi and pledged full U.S. support for Iraqi efforts to reclaim territory from the Islamic State, including by speeding up the provision of U.S. training and equipment, the White House said.
Defense Secretary Ash Carter had said in a nationally broadcast interview aired Sunday that Iraqi forces "showed no will to fight" and fled as the Islamic State advanced on Ramadi. The White House said in a statement that Biden's call "recognized the enormous sacrifice and bravery of Iraqi forces over the past 18 months in Ramadi and elsewhere."
In his remarks at Arlington National Cemetery, Obama said most of the remaining troops should be removed from Afghanistan by the end of 2016.
He recognized the more than 2,200 "patriots" who sacrificed themselves in Afghanistan, including the final two to be killed before the U.S. combat mission ended late last year. He also recognized the first American killed during the "new mission" to train Afghan forces, an Army medic who died in April.
Earlier, troops stationed in that war-wracked country observed a moment of silence in honor of fallen comrades there.
The Arlington observance was among a host of Memorial Day events nationwide featuring parades, picnics and tributes.
Presaging Monday's solemn event at Arlington was the roar of motorcycle engines throughout the nation's capital on Sunday as thousands of bikers saluted veterans with Rolling Thunder's "Ride for Freedom." That was followed by a concert of patriotic music Sunday evening and Obama's private breakfast Monday at the White House with representatives of veteran and military family service organizations. A Memorial Day parade also was held Monday in downtown Washington.
North Dakota marked the 25th anniversary of the groundbreaking for the state's Veterans Cemetery south of Mandan. Gov. Jack Dalrymple directed all state agencies to fly the U.S. and state flags at half-staff, a practice put in place across the country. In South Dakota, Gov. Dennis Daugaard asked state residents to observe the president's request that Americans unite in prayer at 11 a.m. local time and that a moment of silence be observed at 3 p.m. for the National Moment of Remembrance.
Obama traveled by motorcade in late morning from the White House to Arlington and began his outing by laying a wreath at the Tomb of the Unknowns. He bowed his head briefly and listened with others to the playing of "Taps."
Obama said most Americans don't understand the sacrifice made by the 1 percent of the population that serves in the all-volunteer Armed Forces. But when he meets with "Gold Star" families that have lost loved ones through military service, Obama said he hears "their pride through their tears."
"I see that their hearts are still broken, and yet still full of love," he said. "They do not ask for awards or honors. They do not ask for special treatment. They are unfailingly humble. In the face of unspeakable loss, they represent the best of who we are."
Obama said the markers at Arlington signify the blessings many Americans enjoy.
"It's a debt we can never fully repay," he said, "but it is a debt we will never stop trying to fully repay."
Introducing Obama, Carter, the defense secretary, said, "We, your fellow Americans, lack the words to describe what you feel today because try as we may, and try as we do, we can never fully know. But we do know what your sacrifice means to us."
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