“History doesn’t repeat itself,” said Mark Twain, “but it often rhymes.” This is among the reasons we look to the past, straining as best we can through the deepening fog of time to discern lessons for our own day. Analogies to the events that came before are always imperfect, but nevertheless often useful for understanding our present moment. Thus, only a historical myopia can explain why it’s become so common to describe the events involving the covid pandemic as “unprecedented,” even though pandemics have tended to occur every hundred years or so. This nearsightedness is also perilous given, for instance,...