I didn't take the time to delve in to other tweets, but if you know more about him, can you tell me whether, based on what you know of him, he is saying "black people are niggers"(0) or "I won't be shamed into not using a word"(1).

Based on just the tweet, it sounds like #1. If so, I can only repeat "I disapprove of what you say, but I will defend to the death your right to say it". And, furthermore, I don't think that, in itself, says he's racist.