There are a thousand similar threads here on the Forum but.....
"I wanted to see exotic Vietnam... the jewel of Southeast Asia. I wanted to meet interesting and stimulating people of an ancient culture... and kill them. I wanted to be the first kid on my block to get a confirmed kill!
"I felt like putting a bullet between the eyes of every Panda that wouldn't screw to save its species. I wanted to open the dump valves on oil tankers and smother all the French beaches I'd never see. I wanted to breathe smoke."
"Well you did lose a lot of versatile solutions for modern living."
"Well I'm a mushroom-cloud-layin' motherfucker, motherfucker! Every time my fingers touch brain I'm "SUPERFLY T.N.T", I'm the "GUNS OF THE NAVARONE". In fact, what the fuck am I doin' in the back? You're the motherfucker should be on brain detail. We're fuckin' switchin' right now. I'm washin' the windows and you're pickin' up this nigger's skull."
"You go in the cage, cage goes in the water, you go in the water. Shark's in the water, our shark."
"I met him, fifteen years ago. I was told there was nothing left. No reason, no conscience, no understanding; even the most rudimentary sense of life or death, good or evil, right or wrong. I met this six-year-old child, with this blind, pale, emotionless face and, the blackest eyes... the DEVIL'S eyes. I spent eight years trying to reach him, and then another seven trying to keep him locked up for I realized what was living behind that boy's eyes was purely and simply... EVIL."
"I'll make him an offer he can't refuse."
"If anything in this life is certain, if history has taught us anything, it is that you can kill anyone."
I'm sure there are more, but those are the ones that come to mind.