We assess the economic and health costs of COVID and policy responses to COVID. Based on initial estimates of health and economic costs, social distancing policies were justified, but these estimates now seem too high because of learning by doing. Significant differences in mortality rates across US states and countries can be explained by population density, climate, exposure, and policy. Regions that were able to contain the disease early have seen fewer deaths and lower economic losses. Some developing countries initially imposed drastic, costly measures, perhaps motivated by political economy. We also find that there has been underinvestment in prevention and mitigation that could have reduced the cost of adaptation and suggest that there is a lesson for climate change policies.