I'd think the question is if a fatbody XBoxer kid who's done some pot, but who wants to be there, and shapes up, is going to be a better soldier than some draftee who's farm job made him a hardbody but who doesn't want to be there.
Granted, I'm 43, and probably 4F for a bunch of reasons, but as much as I love America, I think I might have a problem being a Mamluk for it.