From my new Upshot column (co-authored with Amanda Taub):

“Everyone is entitled to his own opinion, but not his own facts,” goes the saying — one that now seems like a relic of simpler times.

Today, President Trump is sticking with his own facts — his claim that the Obama administration wiretapped him during the election — in the face of testimony to the contrary by the F.B.I. director, James Comey…

Mr. Trump’s claims may appear to his opponents to have been embarrassingly debunked. But social science research suggests that Mr. Trump’s alternative version of reality may appeal to his supporters.

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. The wiretapping allegations could well become part of a partisan narrative that is too powerful to be dispelled.