Perry's response to Cullivan was as follows..... from the text:
"Am I sorry? If that's what you mean - I'm not. I don't feel anything about it. I wish I did. But nothing about it bothers me a bit. Half an hour after it happened, Dick was making jokes and I was laughing at them. Maybe we're not human. I'm human enough to feel sorry for myself. Sorry I can't walk out of here when you walk out. But that's all." Cullivan could scarcely credit so detached an attitude; Perry was confused, mistaken, it was not possible for any man to be that devoid of conscience or compassion. Perry said, "Why? Soldiers don't lose much sleep. They murder, and get medals for doing it. The good people of Kansas want to murder me - and some hang-man will be glad to get the work. It's easy to kill - a lot easier than passing a bad check. Just remember: I only knew the Clutters maybe an hour. If I'd really known them, I guess I'd feel different. I don't think I could live with myself. But the way it was, it was like picking off targets in a shooting gallery."
In Cold Blood