> But of course, if I adopt a religion's or legal system's idea of morality as my personal compass (certainly the easiest way to go, and easily installed in youth) ... then the distinction falls apart.

That's obviously part of it, but not the entirety of it. Guiding your own behavior is different than feeling compelled to also dictate others' behavior. Honor culture is usually putatively religious, yet is diametrically opposed to "judge not lest ye be judged."

To be fully immersed in it is to feel personally slighted by any perceived transgressions against the normal order of things, and to have zero sense of proportion about which things are truly harmful to all of us, and which things are simply not how we would do things or prefer things to be done.

You were right, zephen is wrong. The "honor" of "honor killings"--which is about prestige within certain sick societies, has nothing at all to do with the notion of being honorable--that is, acting with integrity.