By Matt Underwood like last 20-30 years new. Americans always had their disagreements but in the past most people could at least agree on the problems we needed to address. Now we can’t agree on the problems much less the solutions.
Polarization in the house:
There was always a lot of polarization and differences – they were just regional in the past. And not tied to party affiliation, either. A Democrat in Alabama would be quite different than a Democrat in New York City. Probably more different than Democrats and Republicans in the same state.
Now everyone is all mixed together, and identify more with groups they connect to online than to their neighbors. That’s how you get people flying confederate flags in Pennsylvania, or people in Portland protesting police shootings in Minnesota.
Duverger’s law/effect describes how this polarization/two-party system is inevitable or the natural drawn out effect of simple-majority systems. https://en.m.wikipedia.org/wiki/Duverger%27s_law
I’d like to add, general consensus is that more of the (white) US was ok with segregation and a “laws for thee, not for me” mentality a few decades back, so in this light, polarization is almost (almost) preferable if it means moving away from racist, classist systems.