Well that's really the only bar we have for offensive language, isn't it? If we need a higher bar than that then I suppose we can all just go around insulting each other and expecting nothing to happen as a consequence. Good luck with that.
If you want something more objective, why don't you just ask a sample of people whether they react the same to 'n-word' as they do to the n-word?
I won't let the reaction of a sample of people dictate how I express myself, and I will not hold other people to that standard either.
When did the pursuit of rationality get replaced by the onslaught of feelings? A person can feel insulted, without someone else insulting them. It happens all the time - it's called a misunderstanding. Along the same lines, we may brisk at language not offensive at all, made by people whom through no fault of their own were misunderstood.
And lets not pretend offensive language is not a natural part of how humans (that's us) express ourselves. If it wasn't, there wouldn't be so many swears.
And so we come back to the bigger issue. It is my belief that the society in which I live should be a rational one, and each person in it a rational actor who can distinguish between subtle nuances of meaning, both implied and expressed, and not rely on the stark contrast between allowed and disallowed, accepted or unaccepted. And I fear that if we pursue a mindless list of rules for behaviour, we will be less free for doing so.
We must show humility, knowing that we are not the just judge of each other, and give the benefit of doubt. It is not morally right to participate in a witch hunt on someone for _a word_ said years ago - so I will condemn doing so.
> Well that's really the only bar we have for offensive language, isn't it?
We can construct any bar we'd like.
You seem to completely dismiss concern for the bar being too low, why is that? Lots of people might feel sort of offended by women showing their hair -- should we accept that bar?
If you want something more objective, why don't you just ask a sample of people whether they react the same to 'n-word' as they do to the n-word?