I'll wager a pretty penny that he knew darn well that three purple hearts got you a ticket back to stateside, and that he didn't hesitate to report any such qualifying injuries. And from what I've seen of the creep so far, I certainly don't trust that they were not self inflicted wounds.
I was just a few hundred miles away from him at the same time myself, in USAF uniform. If one really didn't want to serve hazardous duty, and one had the skills to understand the system and use the regs to ones advantage, one certainly would know how to get wounded three times quickly and get out of there. If I ever run for public office (fat chance) you won't hear me bragging about my duty. I served honorably, but not with distinction or bravery.
But at least I didn't spit on my country and fellow soldiers when I got back home.