AT TIMES DESPAIR is hard to resist. Last semester, for instance, at the very moment when my students were reading Nunca más—the report by the Argentine national commission on the disappeared—along with testimonials about the war crimes committed by the military dictatorship, the citizens of Brazil elected a new president who describes the two decades of similar rule in his country as “glorious.” What’s past is prologue, indeed. In this country, as I write these lines, the Bolsonaro rhetoric of violence, racism, and fear is being offered as justification for a government shutdown, as if political debate, democratic power-sharing, and international law were simply obstacles to circumvent, not categorical imperatives. And, even worse, an elected member of the U.S. Congress has asked, in an interview with the New York Times, “White nationalist, white supremacist, Western civilization—how did that language become offensive?...