Cpl. 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 nation'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 valor 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.