It is one of the mysteries of Japan's ongoing nuclear crisis: How much damage did the 11 March earthquake inflict on the Fukushima Daiichi reactors before the tsunami hit?
The stakes are high: if the earthquake structurally compromised the plant and the safety of its nuclear fuel, then every similar reactor in Japan may have to be shut down. With almost all of Japan's 54 reactors either offline (in the case of 35) or scheduled for shutdown by next April, the issue of structural safety looms over any discussion about restarting them.
Plant operator Tokyo Electric Power Co (Tepco) and Japan's government are hardly reliable adjudicators in this controversy. "There has been no meltdown," government spokesman Yukio Edano repeated in the days after 11 March. "It was an unforeseeable disaster," Tepco's then president Masataka Shimizu famously and improbably said later. Five months since the disaster, we now know that meltdown was already occurring as Mr Edano spoke. And far from being unforeseeable, the disaster had been repeatedly forewarned by industry critics. More >>>