MAYBE it was a Monty Python sketch that first introduced the idea of competitive grievance. Four Yorkshiremen tell stories of their deprived childhoods, each trumping the other in exaggerated victimhood. After each sorry tale comes the derisive line: “You were lucky!” Only their grievance matters. It is very funny — but maybe the laughter is fading now as the grievance culture threatens both politics and social harmony. As a doctor recently said to me, “Everyone is just so angry! And I don’t have a cure.” And the doctor’s despair is politicians’ delight; for this is a tide that they can...