Stanley Kubrick said that Full Metal Jacket was not an anti-war movie, just a depiction. There was nothing wrong with Sgt. Hartman, who was just doing a hard job and doing it well since even Pyle graduated. When he says "Since the Marine Corps will live forever, YOU will live forever." he means that.

If you look closely at Animal Mother while he watches Joker shoot the wounded VC sniper, it's Pyle.