Covid-19 has offered some tough but useful lessons about governance. Many wealthy countries did not manage the crisis as well as anticipated, whereas many poorer, populous, and vulnerable countries exceeded expectations. The difference raises important questions not just about public-health management but also about the state of governance in the world’s largest and oldest democracies.

Just before the pandemic, a coalition of major foundations published a Global Health Security Index (GHSI) that ranked countries’ capacity to prevent, detect, and report an infection, and to respond rapidly t...