When Ohio Gov. Mike DeWine announced a ban on spectators at the Arnold Classic, a juggernaut of a sports festival that brings tens of millions in revenue, the move seemed radical. It was March 3, and the state, after all, had not even had a single confirmed case of the novel coronavirus. But within days, large-capacity events were being canceled nationwide. A week later, DeWine recommended that his state’s colleges suspend in-person classes. Across the country, they soon did. He then closed Ohio’s public schools. Other states followed. And on Sunday, DeWine ordered all restaurants and bars be shuttered. By...