Nearly a year after California Gov. Gavin Newsom ordered the nation's first statewide shutdown because of the coronavirus, masks remain mandated, indoor dining and other activities are significantly limited, and Disneyland remains closed.

By contrast, Florida has no statewide restrictions. Republican Gov. Ron DeSantis has prohibited municipalities from fining people who refuse to wear masks. And Disney World has been open since July.

Despite their differing approaches, California and Florida have experienced almost identical outcomes in COVID-19 case rates.

How have two states that took such d...