EconTalk, a collection of podcasts hosted by economist Russell Roberts, is one of the Web's great resources. Among my favorite episodes is Roberts's discussion with Bryan Caplan of Caplan's book The Myth of the Rational Voter. One moment in the podcast jarred me: Caplan refers to "a certain non-economist's* . . . two favorite policies," one of them "a Berlin Wall at the Mexican border" (about 53:12 in). As any educated person who isn't a jackass knows, East Germany built the Berlin Wall to prevent East German citizens from escaping the nation's tyranny; supporters of a wall at the Mexican border (I'm one) want to keep people from entering the US illegally. The former imprisoned, the latter would protect.
Figuring he simply misspoke, I didn't hold Caplan's blunder against him. Then today I listened to (most of) a speech he gave a year or so later in which he uses the same phrase with the same intent (about 34:40 in). And tonight via an Everyzing search I found another podcast in which he uses it twice (about 42:40 and 46:42 in).
Caplan must be a smart man, but every time I hear him refer to "a Berlin Wall" on the Mexican border I think, "This guy's an idiot." If you know Caplan, and he isn't in fact an idiot, please do him and me a favor and suggest to him that he stop employing the image. It should embarrass him particularly because among his primary assertions is that economists tend to be smarter and better-informed than other people.
*Caplan reveals elsewhere that the non-economist is Caplan's father.