"So, what might be driving this tribalism? Psychological research reveals subconscious forces, which – in the face of facts, experience or better judgement – prevent people seeing alternative points of view and push them into ever-more-partisan camps. And some scientists believe that many aspects of 21st Century living could be creating the perfect conditions for falling victim."
One factor overlooked in the USA is the highjacking of one major political party by anti-intellectual, anti-science ideologues, the Republicans.
Politics has never seemed more tribal.