Why is is ok for black people to say the n word but not ok for non-black people to say it to their friends?
It's about reclaiming the word. The 'N' word has a racist past; it was used to discriminate and demean people of colour. By using the word themselves, black people take away the 'N' word's power; they take away it's ability to hurt them. However, the word belongs to them now, and for a "non-black person" to use it, it would be considered an act of racism, unless they have black people's consent to use the word, in which case it would be a thing of friendship, of 'brotherhood' almost. The gay community have done the exact same thing with the words f*ggot and queer. These words have huge homophobic pasts, and by using these words themselves, they take away its power and show homophobic people that it would have no effect on them if they were to use them. I don't know if that's a good explanation, but I'll put it to you this way: Lets say a certain person gets mocked and made fun of because of some certain flaws. But, if that person was to starting making jokes themselves about these flaws, they take the insults' power to effect them, and thus other people stop ridiculing their flaws. By making the jokes themselves, this person just beats you to the punch, so its not fun anymore. Do you get the idea?
YES! That is exactly right.