I was in the military and in my experience people that chose to go into war zones, it's optional, are fucked in the head and literally enjoy killing people, I've seen it a dozen times. They want to kill.
You are absolutely fucking full of shit.
I chose to "go into war zones" many times and none of it was to "enjoy killing people".
You ought to be able to back this up with sources other than trust me bro
Id recommend anyone to give "Generation Kill" series a watch.