The meaning of words depends upon the context that they are used in, and the meaning is the important part.

To use your example of racial slurs: CBC radio broadcast a program about a particular racial slur a few years back. It discussed things like the origin and meaning of the word, how people responded negatively to it, as well as how some people were adopting the word as a symbol of pride (so that it would lose it's power as a slur). The program was framed as an intellectual conversation. There was only one problem: they refused to say the word throughout the program, they said "(letter)-word" instead. If you can't even use a particular word while discussing it, how open and honest can that conversation be?

Now I'm not arguing that we should be using these words gratuitously. We certainly should not be using these words in hurtful ways. Yet there are times when these words can be used to positive ends.