Dunning and Kruger, in a famous series of tests, found that “Incompetent individuals, compared with their more competent peers, will dramatically overestimate their ability and performance relative to objective criteria.” Also: “They will be less able than their more competent peers to recognize competence when they see it — be it their own or anyone else’s.”
While the finding is based on recent work in experimental psychology, it strikes me that Bertrand Russell understood this and expressed it pithily long ago:
The fundamental cause of trouble in the world today is that the stupid are cocksure while the intelligent are full of doubt.
The trouble, of course, is that we (which is to say, voters) take unswerving confidence as a sign that someone is likely to be competent and well-informed, when it’s as apt to signal just the opposite. I suspect this is a big part of the reason we have specialized public policy columnists and pundits, rather than just paying attention to the people with the deepest knowledge of each issue. In part, certainly, it’s that expressing yourself concisely and well to a popular audience is a specialized skill—though perhaps not as difficult as it would flatter us to believe. Rather, it’s that when you call the truly expert folks up for their take, they invariably begin with “It’s complicated,” and then say a lot of things that are hard to squeeze into an 800-word op-ed, let alone a ten second talking point.