In Colorado they have the older standard (before "retreat") which was "shoot 'em INSIDE.
Different places have different standards. It's part of federalism. You don't like federalism go somewhere they don't have it.
If you want to change Colorado law then try to change it.
Regarding the most ancient law, revenge, once you kill somebody's kid it's arrogant and stupid to hang around waiting for it ~ hoping you're a better shot ~ 'cause you're not.
I don't know where muawiyah got that idea (or any of his ideas for that matter) but is totally untrue. Many years ago just after Colorado passed the home defense law it has now there was an incident where a Japanese exchange student was out drinking with his buddies. They stopped at a place they thought was where a party was taking place. Well, it wasn't. The homeowner came OUTSIDE and warned them to go away. The Japanese student approached and kept on coming towards the armed homeowner (WHO WAS OUTSIDE) even after being warned not to. Well, you guessed it the homeowner shot and killed the student. No charges. The law is clear in Colorado concerning self-defense.