Here’s a theory: Trump backers feel personally offended by coverage that suggests they must be stupid to support him. Insulted, they refuse to accept information presented by media outlets that disrespect them.

Think about it: When someone calls you an idiot, then tells you what to do (or not do), do you listen? Even if the instructions are sound, your wounded brain is inclined to tune them out and go the opposite direction.

A study published this week by the Associated Press-NORC Center for Public Affairs Research and the American Press Institute suggests that insulting news consumers is indeed a major problem. In a survey of more than 2,000 people, 38 percent said “yes” when asked, “Have you ever had an experience with a news and information source that made you trust it less for any reason?”

What were the reasons? Factual errors and perceived biases were the top answers. No surprise there. But the third-biggest cause of diminished trust — cited by 24 percent of those who have had a bad experience — was finding “something about the content personally offensive.”