But moral outrage must be closely managed, or it can do more harm than good. Ganz, who eventually became a lecturer at Harvard’s Kennedy School, has spent years teaching people how to use their anger to effect change. Stoking the emotion is easy. Learning how to channel it to useful ends, he told me, is harder. For anger to be productive, at some point, it must stop. Victory often demands compromise. “You have to know how to arouse passions to fuel the fight, and then how to cool everyone down so they’ll accept the deal on the table,” Ganz said.