The kerfuffle over how much authority the president has vis-à-vis state governors boiled over at a recent White House coronavirus briefing. Missing in the debate is the conundrum that became apparent in August 2005, during Hurricane Katrina. During a critical week, from two days before Katrina, to five days after, there arose a conflict the likes of which had never been seen in American disaster governance: an open clash between the president on one side and the Louisiana governor and the mayor of New Orleans on the other. The Depression-Era Heritage. Put simply, the statutes governing emergency authority during disasters...