Defying orders and tempting fate, Marine corporal Dakota Meyer charged five times in a Humvee into heavy gunfire in the darkness of an Afghanistan valley to rescue comrades under attack from Taliban insurgents.

On Thursday, Meyer was presented with the Medal of Honor, the nation’s highest military award, by President Barack Obama.

Meyer’s courage during the six-hour ambush and firefight saved the lives of 36 people, both Americans and Afghans. He killed at least eight Taliban insurgents. Firing from a gun turret on top of the Humvee driven by a fellow Marine, he provided cover for his team, allowing many to escape likely death.

He was defying orders from his commanders, who told him to stay back. The kill zone, they said, was too dangerous. But the young corporal, just 21 years old at the time, knew his friends were trapped that early morning in September 2009.

“In Sgt. Dakota Meyer, we see the best of a generation that has served with distinction through a decade of war,” Obama said during a ceremony in the East Room of the White House.

Meyer, later promoted to sergeant and now out of the Marines, is the third living recipient and the first Marine to be awarded the Medal of Honor for actions in Iraq or Afghanistan.

The modest, soft-spoken 23-year-old now lives in his home state of Kentucky, working construction in the tiny town of Greensburg.

Obama praised Meyer for his humility and work ethic. When the White House tried to reach him in the middle of a workday to tell him his medal had been approved, he worried about whether he could take a call while on the job. So the White House arranged for the president to call during Meyer’s lunch break. With a smile, Obama thanked him for taking the call.

On the eve of the Medal of Honor ceremony, Obama and Meyer met in person, chatting on a patio near the White House Rose Garden, over a beer.

Despite Meyer’s heroism, four Americans died in the ambush: 1st Lt. Michael Johnson, a 25-year-old from Virginia Beach; Staff Sgt. Aaron Kenefick, 30, of Roswell, Ga.; Corpsman James Layton, 22, of Riverbank, Calif.; and Edwin Wayne Johnson Jr., a 31-year-old gunnery sergeant from Columbus, Ga. A fifth man, Army Sgt. Kenneth W. Westbrook, 41, of Shiprock, N.M., later died from his wounds.

Meyer says he has struggled with the national attention, with being recognized for the worst day of his life. He requested that memorial services for those who died that day be held in their hometowns at the same time he received the Medal of Honor.

The president assured Meyer that he had let no one down.

“Dakota, I know you’ve grappled with the grief of that day, that you said your efforts were somehow a failure because your teammates didn’t come home,” the president said. “But as your commander in chief and on behalf of everyone here today and all Americans, I want you to know it’s quite the opposite.”

For all the praise heaped upon Meyer, questions have also been raised about whether the military could have prevented the deaths of the five Americans. Two Army officers were reprimanded for being “inadequate and ineffective” and for “contributing directly to the loss of life” following an investigation into the day’s events.

“You can’t say this with any certainty, but the chances are, in my opinion, that yes they would have been” still alive, said retired Col. Richard Hooker, who led the investigation. Hooker spoke during an interview with CBS’ “60 Minutes.”

Meyer was part of a security team supporting a patrol moving into a village in the Ganjgal Valley on Sept. 8, 2009. Suddenly, the lights in a nearby village went out and gunfire erupted. About 50 Taliban insurgents on mountainsides and in the village had ambushed the patrol.

As the forward team took fire and called for air support that wasn’t coming, Meyer begged his command to let him head into the incoming fire to help.

Four times he was denied before he and another Marine, Staff Sgt. Juan Rodriguez-Chavez, jumped into the Humvee and headed into the fray. For his valor, Rodriguez-Chavez, a 34-year-old who hailed originally from Acuna, Mexico, would be awarded the Navy Cross.

With Meyer manning the Humvee’s gun turret, the two drew heavy fire. But they began evacuating wounded Marines and American and Afghan soldiers to a safe point. Meyer made five trips into the kill zone.