... This is a long standing legal theory that usually dates back to cases where young men in their 20s/30s would get "fighting words" from a significantly older (60s-80s) and then it would escalate into a one sided fight where the young guy would say he did nothing wrong because it was 1) invited and 2) mutual combat or self-defense. It turns on whether a the imaginary "reasonably prudent person" (though no such person exists at all times in all circumstances) would perceive a threat....

...However, since we are bombarded daily with the idea that anyone, everywhere, at all times is a deadly threat, many people earnestly believe any form of perceived threat, actual or otherwise, is justification for another citizen or the state to just shoot someone to kill. People think that it is ok to shoot people just to protect property now (not talking about entering your domicile but robbing cars or a clearly empty building. We are seeing it with property that is not the aggressor's...

... No one is saying a criminal cannot be punished or that you don't have the right to defend yourself. Quite the contrary as even states that require a retreat and/or proportional escalation still allow self-defense claims. There is a reason that spring guns/booby traps are nearly universally banned in the US and have been for some time. Deadly force is not there to protect stuff but people. The reason you can use it when someone breaks in is because it is inherently...

...dangerous to all parties involved when a domicile is broken into (you wake people up in a startle), you expect someone to be living in it, etc., and why you cannot use it when someone is breaking into your barn or a detached building where people do not live without further escalation. We have reached a point where too large a portion of this country thinks it is ok to jump straight to shoot first and ask questions later/just read the card given to you by legal groups ...