I spent four years on a National Academy of Sciences panel on Lessons Learned from the Fukushima Nuclear Accident. I did not expect to learn much new from this collection of essays but was pleasantly surprised by its fresh perspectives.

Gregory Wines, a U.S. security expert, discusses the Maginot Line–type vulnerabilities created by requiring that safety and security be measured against “design-basis accidents” and “design-basis threats.” It was, of course, a beyond-design-basis tsunami that incapacitated the cooling systems of the Fukushima Daiichi Units 1–4. Another chapter by a Stanford group is there- fore devoted to a preliminary comparison of the possibilities of beyond-design- basis floods—by storms as well as tsunamis—of Japanese, European, and U.S. coastal nuclear power plants. The results are interesting enough to merit further systematic independent investigation, including the possibility of flooding of power plants located on rivers, especially in cases in which an upriver dam might fail.

Kazuto Suzuki, a Japanese political scientist, notes that because of continuing legal challenges, Japan’s regulatory system adopted a checklist approach to compliance with nuclear safety requirements. The different levels of Japan’s government insisted to the public—and convinced themselv