he was a fabulist, but he was also a decorated Navy Seal who had a ridiculously accomplished military career.
Something the movie touched on (briefly), and Kyle's life and book show inadvertently, is that he was a guy who suffered majorly from PTSD, but didn't really have a full grasp on how much it had effected him. Yeah, he got kinda kooky there, and because of his death we'll never know why, but we (okay, maybe just me) sure can take a guess as to why.
anyways the whole controversy would have been avoided if Bradley Cooper had shown up the DNC without wearing that beard.