TAYLOR: We drop a lot of bombs then we walk through the jungle like ghosts in the landscape.
"Ghosts in the landscape" eh? As if didn't already have the impression that the guys in the platoon were as good as dead, Taylor gives us a handy simile to help us out: the guys are like ghosts because they're basically dead, the living dead.
RHAH: Whatcha doing in the underworld Taylor?
KING: This here ain't Taylor. Taylor been shot. This man here is Chris, he been resurrected
Taylor has already died once (his entrance into Vietnam was an entrance into the underworld, symbolized by the body bags on the tarmac), and this is his second death, his rebirth as a full-fledged member of the "heads" (the guys who hang out in the underworld and get stoned).
HARRIS: I can promise you something, if I find out there was an illegal killing, there will be a court martial.
Who is Captain Harris kidding anyway? An illegal killing? Good luck with that. His gestures towards there being some kind of rule about killing—about which enemy to kill and not kill—rings kind of hollow in the lawless world of the film, and we know nobody is going to be court martialed.
RHAH: And dig this you assholes, and dig it good, Barnes been shot 7 times and he ain't dead, does that mean anything to you, huh? Barnes ain't meant to die. The only thing that can kill Barnes, is Barnes
Barnes is one of those guys who somehow manages to cheat death over and over again. "Shot 7 times and… ain't dead," as Rhah describes it. He seems destined for immortality. If Platoon makes one thing clear, it's that even the luckiest of fellows, like Barnes, will have to report to the afterlife at some point.
KING: Somewhere out there is the beast and he hungry tonight
The beast isn't hungry for cheese pizza. He's hungry for bodies. The jungle—and the enemy it contains—is a fearsome, cannibalistic machine, a creature that inflicts death on scores of soldiers at a time.
BARNES: Everybody gotta die sometime Red.
Barnes is like Bunny: they both accept the inevitability of death and really don't seem too worried about it at all. Barnes uses this logic to justify things like not allowing O'Neill to take his vacation time, must to O'Neill's frustration.
BUNNY: I told the padre the truth man I like it here. You get to do what you want, nobody f***s with you. The only worry you got is dying, and if that happens, you won't know about it anyway so what the f*** man?
Bunny isn't afraid of death, and he accepts its certainty. For him, death is just a part of life, a part of the Vietnam experience itself. In some ways, he has a point. There's no use worrying about it, he seems to say.