US Corporal William "Kyle" Carpenter took the brunt of a live grenade lobbed by the Taliban in Afghanistan in 2010, saving a fellow Marine's life and nearly losing his own.
On Thursday, the 24-year-old stood beaming and very much alive as President Barack Obama bestowed upon him the Medal of Honor, the United State's highest military award.
"With that singular act of courage, Kyle, you not only saved your brother in arms, you displayed heroism in the blink of an eye that will inspire for generations valour worthy of our nation's highest military decoration," Obama said in a ceremony in the ornate East Room at the White House.
Obama said Carpenter was so badly injured he "should not be alive today." While being treated for his injuries, he went into cardiac arrest and flat-lined three times.
That day in Helmand province, Obama said, Carpenter and Lance Corporal Nicholas Eufrazio, his best friend, were under fire and looking for cover when a live grenade landed near them.
Carpenter has no memory of what happened, but fellow Marines say he lunged toward the grenade and "disappeared into the blast''.
Noted Obama, "Keep in mind, at the time Kyle was just 21 years old. But in that instant, he fulfilled those words of Scripture: 'Greater love hath no man than this; that a man lay down his life for his friends.'''
Carpenter was found face-down, over the blast. His helmet was riddled with holes. His gear had melted and part of his Kevlar vest was blown away.
Still conscious, he asked whether Eufrazio was OK, Obama said.
Carpenter spent five weeks in a coma, waking to what the president called a "gruelling rehabilitation" that involved two years in the hospital. He had brain surgery to remove shrapnel, nearly 40 operations to repair a collapsed lung, fractured fingers, a shattered right arm broken in more than 30 places and multiple skin grafts.
Obama offered: "He has a new prosthetic eye, a new jaw, new teeth - and one hell of a smile."
The president said the South Carolina resident and Mississippi native credited his doctors at Walter Reed in Bethesda, Maryland, for putting him "back together well."
Obama singled out Carpenter's Bethesda medical team for applause and noted that service members in previous wars likely would have died from such injuries.
He saluted Eufrazio, who he said was grievously wounded in the blast and was watching the ceremony from his family's home in Massachusetts.
"Your perseverance is an inspiration," Obama said. "And just as Kyle was there for you, our nation will be there for you and your family as you grow stronger in the years ahead."
The president's remarks came just minutes after he had announced that the US will send military advisers to Iraq to train its security forces to battle Sunni Muslim extremists. He noted that Carpenter was among the Marines who had served in the surge of US forces that he had ordered to Afghanistan early in his presidency.
Carpenter, who became just the eighth living recipient and the second Marine to be awarded the Medal of Honor, is now "just a normal college student" at the University of South Carolina, Obama said.
He's getting "stellar grades," the president said, and he skis, snowboards, parachutes and completed the Marine Corps Marathon. He's an advocate for his fellow wounded warriors and is thinking of majoring in psychology in order to help others, Obama said.
"If any of our wounded warriors seek an example - let me amend that - if any American seeks a model of the strength and resilience that define us as a people, including this newest 9/11 generation, I want you to consider Kyle," the president said.
He doesn't hide his scars, Obama said. "He's proud of them and the service they represent."
The East Room was packed with Marines, members of the Medal of Honor Society - whose ranks Carpenter joined - and a number of South Carolina politicians. Defence Secretary Chuck Hagel sat in the front, and stayed after the ceremony to pose for pictures with service members.
Carpenter - whom Obama described as "still the same humble guy from Gilbert, South Carolina, population of about 600" - said after the event that although "honoured and humbled," he accepted the medal "with a heavy heart''.He said that as the president had draped the medal around his neck, he felt "the history and the weight of the nation". He said he had accepted the award on behalf of all those who have served - including his fellow Marines in Afghanistan.
"If I close my eyes today I can still hear their desperate medevacs being called over the radio," he said. "Today I accept the medal for them. I will wear it for every person who makes up our great and blessed nation."
Carpenter saluted his family and the medical staff "that kept me alive and put me back together."
"I am proud to be a Marine," he said.