Two obvious candidates are New York City and San Francisco, the most densely populated cities in these states and the two densest large cities in the U.S. (Table 1). “As recently as March 10, the rates of confirmed coronavirus infection in New York City and San Francisco were roughly the same: New York City had seven cases and San Francisco had 14. City and state governments communicated a lot better in California than in New York: Compare, for example, the COVID-19 response web pages for New York City and San Francisco.