Going back several years, American media (not just journalism, but social media, film/television, bloggers, etc.) has been pushing out a constant stream of sensational, divisive, identitarian politics and propaganda that overload the intended audience. Here's a very partial list:
1 - Police Brutality - You get a handful of incidents in a year over millions of police interactions with U.S. citizens every single day. And yet the cottage racism industry pushes the narrative loudly and violently that white society is sending out a slave patrol to commit mass murder. What impact do you think that has on a huge chunk of the viewing population?
2 - Income Inequality - Screeching, wailing "progressives" push this narrative that women and minorities are being paid less money for doing the same job as a certain category of men. It's absolutely false and driven by horrible data clustering, but an aggregate number is blasted out at people all the time. What impact does that have?
3 - "Gender Identity" - Numerous major media outlets have been trying to drive home the idea that biology and gender and somehow incompatible concepts, with some school systems even trying to start teaching those ideas to freaking Kindergarteners without parental consent. How do you think these parents react to L.G.B.T. "education" being provided to kids that they haven't even had the basic birds/bees talks with?
4 - White Supremacy - People have been getting hit with this idiocy for about a decade now. If you don't vote for the candidates we endorse, you're a bigot. Disagree with our position/policy for any reason at all, and you're a bigot. The constant accusations that every Caucasian citizen bears direct, unqualified responsibility for racial disparities in education, health outcomes, crime, and wealth. Surely we can see how this would impact viewers on all sides of the debate.
The constant pounding of these messages in every form of media imaginable has escalated tensions to an enormous level at this point.