The curious mind of Pete Buttigieg holds much of its functionality in reserve. Even as he discusses railroads and airlines, down to the pointillist data that is his current stock-in-trade, the US secretary of transportation comes off like a Mensa black card holder who might have a secret Go habit or a three-second Rubik’s Cube solution or a knack for supplying, off the top of his head, the day of the week for a random date in 1404, along with a non-condescending history of the Julian and Gregorian calendars.

As Secretary Buttigieg and I talked…