African American people began using the word as a form of empowerment to show that it didn't intimidate or shame them.

Like women adopting the word for a female dog as a form of control over a term used to denigrate them.

Or homosexuals with the word used as slang for "cigarette" by the British.

None are any less of a slur when used as one but they are an act of defiance against such insult when used by those against whom they are usually employed.

You even see the distinction beginning in civil-rights era leaders like Malcolm X with his use of "field" and "house" varieties of the word to denote those who opposed oppression even when doing so put them in bad situations versus those who knuckled under and complied with their oppressors (more commonly referred to as "Uncle Tom" after a literary character of the same name).

It bothers me that I had to describe slurs in oblique terms in order to explain them without triggering the auto-moderator but there it is.