America has always been a racist country, but until recently (in the modern era) we didn't discuss it in "polite" company. Now, social media has created a "hive mind" among us, so the racism that was always there is clear and obvious. And Trump knows it, and is using it to connect with others in his part of the hive.

Making things worse, the algorithms the social media companies use cause everybody to think their own part of the hive is larger and more "real" than it is, so it actually does get amplified as it brings in "the unconverted" - people who would previously have rejected such thinking or speaking.

This is how the racists, misogynists, homophobes, and other bigots have so rapidly acquired both power and platforms for their hateful speech.

-Thom