Map of the east coast of Japan showing the distance between Tokyo and Fukushima Daiichi, 150 miles to the north.

A new independent report on the Fukushima Daiichi Nuclear disaster reveals that Japan’s Prime Minister Naoto Kan feared events following the March 11, 2011 Tohoku earthquake and tsunami would require the evacuation of Tokyo. The report, conducted by the Rebuild Japan Foundation, a new policy organization comprised of college professors, journalists and lawyers, sheds new light on just how in-the-dark many were in the wake of natural disasters that left the Fukushima nuclear facility with damaged safety systems and without internal or external power.

The investigation underscores the conflicting interests of the Japanese government, the directors of Tokyo Electric Power Company (TEPCO–Fukushima’s owner and operator), and those on the scene at the crippled nuclear plant. Masataka Shimizu, president of TEPCO, is said to have ordered all of Fukushima Daiichi’s employees to evacuate the facility in the days after March 11, but Daiichi’s plant manager, Massao Yoshida, argued that he could get the damaged reactors under control if he and nuclear workers remained. PM Kan eventually ordered a skeleton crew to stay at the plant, fearing that Fukushima Daiichi, the nearby Fukushima Daini and a third nuclear facility could spiral out of control and start what has been translated as a “devil’s chain reaction” or a “demonic chain reaction” that would necessitate evacuation of the nation’s capital, a city of 13 million people, 150 miles south of Fukushima prefecture.

Given this new window on internal deliberations (far too nice a word–these were likely frantic, heated arguments) in Japan, the decision made by US Nuclear Regulatory Commission Chairman Gregory Jaczko within days of the quake to recommend evacuating American citizens from an area 50 miles around Fukushima seems downright conservative. In recent days, nuclear power proponents have used this action as their latest volley in their ongoing push to oust Jaczko and replace him with a more servile chief regulator.

Interesting, too, the objections of TEPCO’s president to the plan to pour seawater on the melting Fukushima reactors and boiling spent fuel storage pools. This last-gasp measure, apparently the idea of Yoshida, the Daiichi manager, is believed to have somewhat cooled the reactors and at least kept the fuel pools from completely emptying–which would have resulted in a much more serious outcome (hard to believe, but true)–though it should be noted that the radioactive runoff is now contaminating the ground, groundwater, rivers and the ocean around Fukushima. TEPCO brass no doubt did not want to use seawater because its corrosive effects would make it impossible to ever restart any of the Daiichi reactors (again, ridiculous in hindsight, but not hard to imagine inside the profit-above-people distortion bubble that exists at companies like TEPCO). (UPDATE: Japan Times reports Kan was reticent to use anything but fresh water, but Yoshida ignored him and went ahead with the use of seawater.)

Other recent revelations–about how close Fukushima Daini came to a meltdown of its own, about how the Fukushima region is now more seismically unstable, and that the government had dire assessments of the disaster that it worked hard to keep secret–serve to buttress Naoto Kan’s fears that a string of nuclear disasters was a distinct possibility. And it should also serve as a warning that those fears are still a possibility if the region’s nuclear plants–whether or not they are still functioning–are not decommissioned and contained.

And all this information, and the new details on the lack of trust between the Japanese government and TEPCO, also paints a more nuanced–and, honestly, disturbing–picture of the environment in which US officials had to make decisions.

But, perhaps most importantly, this latest report is yet another data point against the absurd assertion that Fukushima Daiichi somehow proves nuclear power’s “defense in depth” safety systems work. The assertion that Fukushima isn’t a massive disaster, just as it stands today, is ridiculous, but reading about the lack of good information in the early days of the crisis, the internal fights and the government’s fears makes it clear that things could have easily been much, much worse. While there are still real concerns about just how much radiation residents throughout Japan will be expected to absorb, and there are still many technical questions that remain unanswered, it now appears that it was only a combination of an occasionally assertive PM, the heroism of about fifty Daiichi workers and maybe some dumb luck that gave the world the relative luxury of calling Fukushima an ever-metastasizing disaster, rather than an almost-instant hell on earth.