Air travel is one of those topics that no radio or TV show can go wrong with — it’s certain to touch a nerve with many people and provoke numerous comments and questions. That’s what happened yesterday on NPR’s Diane Rehm Show, which I was on for the first time.

I always thought the reason to be invited would be to talk about foreign policy on the Friday news roundup, where Diane has three Washington journalists discussing issues from the passing week. That never happened, but a couple of weeks ago I suggested to one of the show’s producers that the summer is a good time for a program on travel…