It sounds like he's also referencing the old and tired racist tactic of arguing that they don't hate black people, just the ones who are "acting like niggers",

It sounds like he's also referencing the old and tired racist tactic of arguing that they don't hate black people, just the ones who are "acting like niggers", and turning that argument back on the people who use it. (Also, the use of slurs isn't verboten period. It's still - so far as I can tell - within the bounds of publicly-acceptable discourse for people with the correct political views to refer to black people with the wrong, conservative views as "niggers" and every other slur. Possibly even whilst threatening violence against them.)