What America needs to do before lockdown can end

Most of the world outside the United States has reached the end of the beginning of the novel coronavirus pandemic. New confirmed infections and deaths have plateaued and are beginning to fall in some of the hardest-hit countries like Italy and Spain, and Germany is beginning to draw up plans for re-starting its economy. (It seems that only Brazil, with its crackpot far-right president Jair Bolsonaro, is failing as badly as the U.S., with perhaps the U.K. in a close second.)

We're beginning to see a glimmering of what it...