This is an excellent read that precedes the TED talk, which also makes for good viewing. In a very systematic way, Dr. Huemer reasons through why people consistently are irrational in their political viewpoints, and talks about ‘belief fixation’ and some of the implications. He provides some ideas on how to navigate these situations, knowing their irrational nature. Excellent reading for considering why the 2016 election turned out how it did.
https://rintintin.colorado.edu/~vancecd/phil3600/Huemer1.pdf