Early in the invasion of Iraq in 2003, I spent a scary, violent day with U.S. troops, and that night we watched a feed of Fox News — and our jaws dropped as commentators ridiculed critics of the invasion and blithely insisted that Iraqis were welcoming us as heroes. The troops and I looked at each other in astonishment.

The right-wing media bubble and its conspiracy theories can even be lethal. During the 2009-10 swine flu epidemic, Democrats and Republicans initially expressed roughly equal concern. But then conservative commentators denounced the Obama administration’s calls for vaccination as a nefarious plot. Glenn Beck, then of Fox News, warned that he would do “the exact opposite” of what the administration recommended.

As a result, Democrats in the end were 50 percent more likely to seek vaccination than Republicans, according to the Journal of Health, Politics and Law. Some 18,000 people died in that flu epidemic, so it seems logical that some died because they believed Fox News.