鈥淭he common good.鈥 The phrase may sound out of tune with the harsh tone of America鈥檚 public square. But it crops up in Patrik Jonsson鈥檚 story today about professional work and citizen alertness. That鈥檚 what led law enforcement to Luigi Mangione, who has been arrested on weapons charges and is a suspect in the killing of UnitedHealthcare executive Brian Thompson. Many people anonymously and darkly cheered him on. But Patrik鈥檚 sources said that Mr. Mangione may have underestimated something else at work: a deeper respect for the common good.