Harvard historian Moshik Temkin thinks "Historians Shouldn't be Pundits." He's worried about eggheads doing "thirty-second blasts" on the tube based on superficial analogies—like Trump channeling Hitler, for instance. Rather, Temkin wants "politically engaged" historians to ask the tough questions, like "How did a rich guy who never contributed a thing to the public good become a public figure?" Amateurs unfamiliar with the catechism of professional historiography may be forgiven for not immediately grasping the distinction he is making here. But here's a clue gleaned from Volker Ullrich's superb Hitler: Ascent 1889-1939. Hitler was not "a rich guy."