A couple of people have made this argument but it makes no sense. I've BEEN in situations where I couldn't walk away.

Those situations, where my physical safety was at risk, weren't made any better or worse because the person threatening me used the n-word. They could have been quoting poetry at me, but what difference would it have made if they were about to attack me?

You're confusing the power of the physical danger with the power of the words used alongside it. They're not related.

And I don't mean to be condescending, but if you imagine that the kind of person who is going to physically attack a black person whilst using racial slurs will think twice about their language because of social backlash, I don't think you've thought the situation all the way through.