President Obama awarded the Medal of Honor on Thursday to Marine Cpl. William “Kyle” Carpenter, celebrating the veteran’s heroism and the modern medical miracle it took to keep him alive after he was rocked by a grenade blast while trying to shield a fellow Marine from harm.

Carpenter, 24, received the award in a ceremony in the East Room of the White House, flanked by his family and dozens of Marines from his unit. He is credited with deliberately lunging at a hand grenade that an insurgent threw at him and another Marine, Lance Cpl. Nick Eufrazio, while they manned a rooftop security post in a small, dusty compound in Marja, Afghanistan.

Carpenter still bears the scars of that Nov. 21, 2010, attack but has made a remarkable recovery. He has run a marathon, sky-dived and completed a mud-run competition since being injured, the president noted, and pushed through physical therapy and surgeries to retire medically and attend the University of South Carolina.

“You’ll notice that Kyle doesn’t hide his scars. He’s proud of them and the service they represent,” Obama said.

In a lighter moment, the president added: “And, now, he tells me this, and I’m just quoting him: He says the girls like it. So he’s working an angle on this thing. I wasn’t sure I was supposed to say that in front of Mom.”

The fact that Carpenter was able to laugh in response is a testament to modern medicine and quick work by his doctors and his fellow service members. Carpenter’s vital signs flat-lined numerous times after he was injured, Obama recalled, but the Marine was resuscitated each time.

“I want you to consider what Kyle has endured just to stand here today: More than two and a half years in the hospital; grueling rehabilitation; brain surgery to remove shrapnel from his head; nearly 40 surgeries to repair a collapsed lung, fractured fingers, a shattered arm broken in more than 30 places; multiple skin grafts,” Obama said. “He has a new prosthetic eye, new teeth, and one hell of a smile.”

The president recognized two doctors — Debra Malone and Lauren Greer — and other medical staff at Walter Reed Army Medical Center in Bethesda, Md., who have been instrumental in healing Carpenter.

“Today is also a reminder that in past wars, somebody with injuries as severe as Kyle’s probably wouldn’t have survived,” Obama said.

During the ceremony, Obama acknowledged the 2010 deaths of two of Carpenter’s friends and fellow Marines, Lance Cpl. Dakota Huse and Lance Cpl. Timothy Jackson. He added that Eufrazio is still recovering from injuries he sustained in the blast and was watching the ceremony with his family in Plymouth, Mass.

After the ceremony, Carpenter told reporters that he was honored and humbled to accept the Medal of Honor but did so “with a heavy heart.”

“As the president put the medal around my neck, I felt the history and the weight of a nation,” he said, recalling Marines who fought everywhere from the trenches of World War I, to the icy battlefields of Korea, to cities in Iraq such as Baghdad, Ramadi and Fallujah.

“I think about the Marines who were with me in Marja,” he continued. “If I close my eyes today, I can still hear their desperate medevacs being called out over the radio as they bled out in the fields of Afghanistan. Today, I accept the medal for them. I will wear it for every person who makes up our great nation.”