White nationalism is indeed a major problem in ICE (and law enforcement in general), but I don't think this is an accurate way to paint the situation as a whole. This is what textbook nativism looks like, and many non-white americans are nativists as well. They rhyme and overlap and often share goals but they're not the same and they are often motivated by different fears.

What we see here looks more like this than like apartheid/jim crow (though if you look at how we treat legal immigrant labor it gets much blurier): https://en.wikipedia.org/wiki/Operation_Wetback