If you are going to define which term to use, you can use any one you want. I doubt whites using the term "Negro" are using it because it is proper.
It just goes to show you how leftism has coopted the language in an Orwellian fashion. And like another poster stated, these racist group(s) have changed what they want to be called at least 5 times during my lifetime as well. They can't even make up their own mind. None of which were ever insults at all.