Some places become synonymous with tragedy, with catastrophe: Hiroshima, Chernobyl, Flint, Aleppo. On March 11, 2011, Fukushima joined that list. After a 9.0 magnitude earthquake struck Japan, the worst in its history, the nuclear reactors on the Fukushima Daiichi nuclear power plant automatically shut down. A tsunami soon followed, with waves up to 40 meters high; in Fukushima prefecture in northeastern Japan, it disabled the emergency generators intended to provide power to cool those nuclear reactors.

Inadequate cooling led to three nuclear meltdowns. The plant spewed radioactive material...