The possibility of U.S. lockdowns—never attempted on this scale in the history of pandemics—was already in the air in early March 2020. The theory of lockdown had been floating around for 15 years but now China was first to try it, and claim enormous success, however fraudulently. Incredibly, the United States was set to try it out too but getting Trump on board was going to take some doing. The federal government had the quarantine power since 1944. That much we knew. But just how expansive could its exercise be? Would they dare quarantine the well with the sick? How...