[mynameishere]

Are you sure you can run all those calculations while breaking and entering is occurring in your home? It varies quite a bit from place to place, as you can see...

https://en.wikipedia.org/wiki/Castle_doctrine

But the basic idea is that the natural right of self-defense extends to certain areas, including one's home. (That is, you do not have to wait until the intruder has his hands around your neck in order to defend yourself.) If you would prefer to not be allowed to defend yourself, that's you. In many countries (not just the US) invading people's homes makes for a dangerous and short career, as it should.

[wizofaus]

Thanks for that link, that is pretty interesting and I can't honestly say I know exactly what the law is where I live (in Australia, but not in the state that gets a special mention in that article). And absolutely, if I happened to have access to a lethal weapon and I was sufficiently fearful I might well be tempted to use it on an intruder even well before they posed an immediate threat. But if I really were responsible for taking an intruder's life and the courts determined that they were never a realistic threat to anyone, nor was there any good reason for me to believe they were (e.g. I had a clear view of them, could see that had no weapon, and they weren't acting in any sort of hostile manner), I'd fully expect to go to jail for it.