This week on my podcast, I read a recent Medium column. “Ideas Lying Around,” about archivillain Milton Friedman’s surprisingly good theory of change, and how to apply it to progressive politics.

Enter Friedman: to people reeling in crisis, Friedman insisted that the missing oil was somehow the product of unionization, pollution controls, women’s lib, and the civil rights movement. Though this was transparent nonsense, akin to blaming witches for a crop failure, the crisis was so dislocating,...