What's the real problem with calling Africa and Haiti sh*tholes?

There's a history in racist circles of using skin color to associate African people with sh*t. That doesn't show up in public much, not in recent decades, but it's still there and you can be sure the sheet-wearing crowd still uses it. Trump has definitely heard it, if he doesn't use it himself. So that's what came to his mind when he decided to insult black-majority countries.

Think about it, he thinks Mexico and Panama and Philipines are terrible places. But he didn't think of calling them sh*tholes because they aren't majority black.