Epidemics, it seems, can have mercurial effects on a stricken state’s politics. President Xi Jinping could face a backlash within the Chinese Communist Party, just as factional strife wracked the Athenian assembly. Xi could be unseated, he could launch a crackdown that consolidates his rule, or events could take some unforeseeable course. There is no guarantee, furthermore, that a China battling the coronavirus will be an introspective China, or a cautious one in military affairs. Depending on the trajectory domestic politics takes, China could embark on venturesome if not reckless policies toward its neighbors—much as Athens defied political and strategic logic, hurling itself into fresh enterprises despite its weakened state. Conditions in China, in other words, bear close monitoring—and not just in the interest of containing disease.

And then there were the malady’s social, cultural, and religious effects. Thucydides recounts how plague severed the ties of fellow-feeling—what Kagan calls “the most sacred bonds of civilization”—that held Athenian society together. Despair—to my mind a fifth horseman of the Apocalypse—ran rampant among Athenians as disease raged within the walls and enemies pillaged outside. Sickness and death were lonely experiences. No one wanted to contract the disease, so everyone shunned the infected. Meanwhile lawlessness took hold throughout the city. Few saw much point in obeying divine law, as the righteous appeared as prone to sicken and die as the licentious. Nor was there much point in obeying civil law; why bother when offenders would never live to stand trial anyway?

As moral and ethical strictures collapsed, Athenians gave vent to their basest impulses and excesses. All manner of riotous living ensued. Why not indulge today if tomorrow you die?