… Partisan polarization is now so extreme in the United States that it affects the way that people consume and understand information — the facts they believe, and what events they think are important. …
Mr. Trump, perhaps unconsciously, has grasped a core truth of modern politics: that voters tend to seek out information that fits the story they want to believe, usually one in which members of the other party are the bad guys. …
People are more likely to believe stories that come from their side of the political divide, particularly if an authority figure vouches for them. And they are more likely to share news with their preferred slant as a way of showing they are good members of their political tribe. CONT.
Amanda Taub & Brendan Nyhan, New York Times