This is, unfortunately, what happens when a nation is ideologically divided. When the level of division is low, these things happen infrequently, when a more extreme person comes into power. Once the divisions get bigger, the deliberate provocations become more common, until the culture of each side starts to shift, viewing the other as really an enemy. Then the abuse becomes unconscious and insidious.

From the few years that I lived in the USA, it was already pretty palpable, the disdain and borderline hostility between conservatives and liberals, with some of the strangest stories of outrage flying from each's lips regularly. TBH I had trouble telling the two apart, other than that one kind I saw in California, and the other next door in Arizona.