he almost had a smile on his face. >> reporter: did you ever see him again? >> i never saw him again. one month later, he passed away at walker reed. osama bin laden was killed in 2011, but the war ground on. in 2012, we visited the wounded at walter reed, where amputations, many of them multiple were running at more than 20 a month. >> what was the damage? >> both legs amputated. >> reporter: staff sergeant eric meyers was on his third tour in afghanistan when he stepped on a booby trap. >> most of the people back here think the war is winding down. >> for those on the ground it's not winding down. it's still just as intense as it was. >> reporter: the hard truth at walter reed was that afghanistan changed them more than they changed afghanistan. now the war has come full circle. major general chris donahue, the last man out of afghanistan, was a junior officer serving in the pentagon on 9/11.