Edward L. Glaeser joins Brian Anderson to discuss the implications of the Covid-19 pandemic on city life in America, the connection between urban density and contagious disease, how to prepare for the threat of future outbreaks, and the economic-policy response of leaders in Washington. As New York enters its second month under effective lockdown, Glaeser reminds us that "density and connection to the outside world—the defining characteristics of great cities—can also turn deadly." Contagious disease has always been the enemy of urban life; overcoming it in the past has required massive investments in sanitary infrastructure. The current pandemic could prove a long-run disaster for urban residents and workers unless public fear is alleviated.