You totally lost it at the end...

Killing for satisfaction qualifies as psychopathy as much as killing for one's country or defending one's child.

How is defending one's child and killing the attacker in the process in any way related to the other two cases (for satisfaction, which is emotion, or one's country, which is a concept)?

Killing in self-defense is instinct. There isn't even to need to intellectually process it, you react, as if a car is about to hit you and you jump away.