Firstly, you're confusing morality with legality.
Secondly, you're confusing doing something in self-defence and doing something and not getting caught.
Thirdly, "nothing's illegal unless you get caught" is wrong. Just plain factually wrong. It's a pseudo-philisophical phrase that doesn't mean a thing.
That said, you're both idiots. None of the last half-dozen posts are remotely relevant to the thread and if you two would like to debate morality, ethics, and law with your knowledge gleaned from Law & Order re-runs and what you recall from reading some Aristotle in high school then please, please, do it in private messages so the rest of us don't have to suffer the embarrassment of seeing it.