Japan could be building an irresistible terrorist target, experts say

The country has balked at U.S. security advice for its nuclear plants

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Rokkasho in winter: The $22 billion plant is designed to produce 8 tons of plutonium a year, enough to fuel more than 2,600 warheads

Kyodo News, Yumi Ozaki/AP

ROKKASHO, Japan — Sporting turquoise-striped walls and massive steel cooling towers, the new industrial complex rising from bluffs astride the Pacific Ocean here looks like it might produce consumer electronics or bath salts.

But in reality it is one of the world’s newest, largest, and most controversial production plants for a nuclear explosive.

The factory’s private owners said three months ago that after several decades of construction, it will be ready to open in October, as part of a government-supported effort to create special fuel for the country’s future nuclear power plants.

Japan’s leaders affirmed last month they intend to proceed with that effort, a decision that has stoked anxiety in East Asia and set off alarms among Western experts who worry about the spread of nuclear weapons technology — including some inside the Obama administration.

Once it is running, the plant will produce thousands of gallon-sized steel canisters containing a flour-like mixture of uranium and plutonium, enough in theory to provide the building blocks for a huge nuclear arsenal.

Publicly, the United States has said little about Japan’s plans to enlarge its already substantial hoard of plutonium. Washington formally granted Japan the unlimited right to use U.S. technology and nuclear feedstock for the plant during the Reagan administration. Now some of that materiel is to be returned, under a deal to be announced later this month at a U.S.-led international summit in the Netherlands promoting the security of nuclear materials that can be used as explosives.

It all sounds calm and cordial. But since Obama was first elected, Washington has been lobbying furiously behind the scenes, trying to persuade Japan that terrorists might regard Rokkasho’s new stockpile of plutonium as an irresistible target — and to convince Japanese officials they should better protect this dangerous raw material.

Specifically, U.S. officials have struggled, without success so far, to persuade Japan to create a more capable security force at the plant than the white-gloved, unarmed guards and small police unit stationed here now. They also have been trying to persuade the privacy-minded Japanese to undertake stringent background checks for the 2,400 workers employed here.

It’s been a hard sell for Washington, according to experts and officials in both countries familiar with the diplomatic dialogue. With U.S. prodding, Japan has gradually heightened security at Rokkasho and other nuclear sites, but officials in Washington say they remain worried that the improvements are too slow and incremental.

The dialogue highlights a vast gulf in the two countries’ security cultures. Japan has been far less ready than the United States to imagine and prepare for nuclear-related disasters; its federal agencies have deferred to state and utility officials on safety and security issues; and its political leaders have shown little interest in cooperating with U.S. and other Western experts to improve its standards.

Some Japanese officials have told their American counterparts that the homogenous, pacifist nature of their society makes nuclear conspiracies unlikely — a conclusion that U.S. officials and independent experts categorically reject. Other Japanese officials have insisted that in a nation where gun ownership is rare and privacy rights are zealously guarded, armed guards and background checks are unacceptable at even at the riskiest sites.

“It is a system that relies heavily on the expectation that everyone will do what they are expected to do,” said a senior Obama administration official, who asked not to be named while speaking about a sensitive diplomatic issue. As a result, “the stuff we would kind of expect to see” at a dangerous nuclear facility “is not there.”

A consortium of electric utilities, Japan Nuclear Fuels Limited, has spent 22 years building the plant, the cornerstone of a plan to build the world’s first energy system based on plutonium-powered, fast breeder reactors. (Breeder reactors — a technology considered and rejected in the United States more than 30 years ago — are so named because they can produce more plutonium than they consume.) Japanese consumers are paying the $22 billion bill for its construction through a surcharge on their electric bills.

When the Nuclear Fuel Reprocessing Center at Rokkasho is operating at full capacity, it’s supposed to produce eight metric tons of plutonium annually. That’s enough in theory for a country like Japan to make an estimated 2,600 nuclear weapons, each with the explosive force of 20,000 tons of TNT.

When the Rokkasho plant was conceived, Japan believed plutonium-burning reactors would make the island nation energy independent. The facility was embraced as a way to convert nuclear wastes into fuel on a crowded archipelago rocked by violent earthquakes, dotted with active volcanoes, and lashed by tsunamis and typhoons.

Critics of the plant point out, however, that Japan has no urgent need for a single kilogram of the plutonium the plant will produce.

Already, Japan has 9.3 metric tons of plutonium stored at Rokkasho and nine other sites in the island nation, along with around 35 tons of plutonium stored in France and the United Kingdom. Altogether, Japan has the fifth-largest plutonium stockpile of any nation, representing nine percent of the world’s stocks under civilian control.

Included in that figure is 331 kilograms — 730 pounds — of high-grade plutonium, the kind preferred by weapons designers, that Japan has agreed to send to the United States. It was sent there by the United States and Britain in the 1960s and 1970s to assist researchers.

Once Rokkasho opens, the size of this stockpile could easily double in five and a half years, because by the government’s own forecast Japan is at least 20 years from completing the first of the commercial reactors designed to burn the plutonium that Rokkasho will produce.

The Japanese government has a backup plan to burn a mixture of Rokkasho’s plutonium and uranium in a third of Japan’s 48 operable light-water power reactors. But after the tsunami-provoked nuclear disaster at Fukushima in 2011, all of those reactors have been closed. And if they are reopened, perhaps beginning later this year, the communities that host them may be wary of letting the reactors burn plutonium-laced fuel, Japanese political analysts say.

In its familiar dull-gray metallic form, a pound of dense plutonium takes up much less space than a pound of lead. A lump weighing a little more than six and a half pounds — enough to make a weapon — is the size of a grapefruit. The point, critics say, is that an eight-fluid-ounce thermos full of the metal in the wrong hands could produce a devastating terror attack.

Long resistance to U.S. pressure

After a U.S. embassy science officer witnessed a security drill in 2006 at the Mihama nuclear power plant along Japan’s northern shoreline, the officer sent a classified cable back to the State Department noting the typical police presence: “a lightly armored police vehicle with up to six police officers — some of them fast asleep.”

This sardonic observation, which appeared in a cable published in 2011 by Wikileaks, came after years of prodding by Washington for tougher security around Japan’s nuclear installations. The U.S. campaign was inspired partly by America’s discovery in 2002 that the 9/11 attackers had initially considered a plan to crash planes into U.S. nuclear power plants.

The U.S. Nuclear Regulatory Commission responded by ordering U.S. plants to improve physical security, tighten access, improve guard training, and compose new emergency response plans. Security forces grew by 60 percent, to about 9,000 officers, according to the Nuclear Energy Institute. Washington also pressed others, including France, Britain, Russia, Japan and China, to take a similar get-tough approach.

But in Japan, at least, there was resistance.

Paul Dickman, a former Energy Department official and chief of staff to the chairman of the Nuclear Regulatory Commission under President George W. Bush, says that when he asked a Tokyo Electric Power Company official after 9/11 why the company hadn’t toughened security measures faster at the Kashiwazaki-Kariwa plant, the world’s largest nuclear power station, he was surprised by the reply.

“We are in the process of making those changes, but we don’t want to do them all at once because we don’t want people to think that we have been operating them unsafely in the past,” the official said, according to Dickman.

Kevin Maher, the chief science and technology officer at the U.S. embassy in Tokyo from 2001 to 2005, said that when he and White House homeland security adviser Frances Townsend met there in 2005 with a senior official at Japan’s Nuclear and Industrial Safety Agency, “We told him, ‘Your nuclear power plants are very good targets’ ” for terrorists and that security urgently needed to be tightened.

Maher cannot recall the official’s name but distinctly recalls the reply: The official said, “There is no threat from terrorists because guns are illegal in Japan.” Maher said Townsend turned to him and asked: “Is he joking?” The official’s view, he said, was widely shared inside the Japanese government.

“That’s what we were up against,” Maher said.

Townsend, in an interview, confirmed the account and said her impression was that “the Japanese thought of themselves as very much isolated from this particular threat, that it was an American concern that didn’t touch them.”

The Mihama drill, the first of its kind in Japan, included 2,000 participants, including local residents, industry officials, members of the Self-Defense Forces, and some police. But they followed a tightly-written script “with no surprises thrown in,” the U.S. science officer said, and the exercise lacked a simulated attack.

The motive for the drill, the diplomat wrote, was fear of a mortar attack against nuclear plants by North Korean saboteurs who could readily reach the Japanese coastline. But there was no “force-on-force” simulation like those routinely included in U.S. exercises. The diplomat concluded Mihama’s security system had shortcomings, noting that a local nuclear safety official admitted “that his office had no contact with the local police on plant security issues.”

Two years later, when U.S. Chargé d’Affaires Joseph Donovan expressed his own, broader concerns to two deputy safety directors at Japan’s Science and Technology Ministry, they responded that the contract guard forces at Japan’s nuclear facilities are “prevented by law from carrying weapons,” according to a confidential cable Donovan sent to Washington.

When he specifically challenged the absence of armed guards at a Japanese research center stocked with plutonium and weapons-grade uranium sent from the United States and Britain in the 1960s, the officials “responded that an assessment of local needs and resources had indicated that there was not a sufficient threat to justify armed police” there, according to the cable, also published by Wikileaks.

The deputies said further that background checks for plant workers were unconstitutional and that the government wanted “to avoid raising what is a deeply sensitive privacy issue for Japanese society.” But they also said some checks might be going on “unofficially.”

The situation has hardly improved since then, the senior Obama administration official said in a recent interview, speaking on condition of anonymity due to the sensitivity of such conversations. The devastating accident at Fukushima showed, he said, that police and lightly-armed Japanese Coast Guard forces play a secondary role in security and safety emergencies to private, unarmed security guards. The Japanese government, he said, is heavily dependent on what the utilities decide to do.

The official added that although Japan has recently staged counter-terror exercises at nuclear plants, including Rokkasho, and allowed some Americans to watch, “they remain very heavily scripted.” The aim is not to embarrass anyone. “There is great sensitivity to that,” the official said.

John Thomas Schieffer, the U.S. ambassador to Japan from 2005 to 2009, said Japan’s approach to nuclear security can be explained partly by its history. During the Second World War, the Imperial government’s huge domestic intelligence apparatus — including the notorious Military Police Corps — kept a close watch on all Japanese citizens.

“They didn’t want to return to the sort of police state they had during the war,” Schieffer said. Also, “the Japanese had a hard time in the beginning conceptualizing that somebody would want to do something in Japan that would result in a loss of life.”

Another former State Department official who served in Tokyo in the 2000s noted that “their view was that they had everything under control. They lived on an island. They had very few enemies. They were just looking at this from an entirely different perspective than us.”

A pacifist culture?

Since the 9/11 attack in the United States, every nuclear power station in the United States has been required to conduct mock “force-on-force” exercises involving a team of guards pitted against a team playing the role of terrorists. The attackers are assumed to be suicidal, highly trained, armed with explosives and automatic weapons and bent on causing the release of deadly fallout.

The Japanese conduct no such exercises, explaining that such an attack is improbable in their country.

Terrorists of course have used truck bombs to devastating effect in Grozny, Nairobi, Baghdad and Oklahoma City. The U.S. Nuclear Regulatory Commission said 33 years ago that a large truck bomb directed against a nuclear reactor in an urban area could kill 130,000 people. The threat is one of just four specifically mentioned — along with boat bombs, insider thefts and cyber-attacks — by the NRC’s director of preparedness and response, in an Aug. 2013 posting about security issues raised by the Fukushima accident.

Assaults on nuclear facilities are rare, but not unknown. According to a 2013 report by Alan Kuperman, a proliferation expert at the University of Texas-Austin, intruders have attempted to gain access to or blow up reactors or other nuclear facilities in Russia, South Africa, Lithuania, South Korea and elsewhere.

Matt Bunn, a former White House official now at Harvard University, said it’s unrealistic to believe that a terror attack in Japan is improbable or unlikely to succeed.

In Sweden, another country that sees itself as relatively nonviolent, Bunn noted, a gang with Serbian connections in 2009 flew a stolen helicopter to raid a cash depot for restocking ATMs, blasting down doors with explosives to steal $5.3 million. “Just because you’re a very safe country doesn’t mean bad guys [connected to]…other countries won’t come and take your nuclear stuff,” Bunn said.

Japanese Red Army hijackers commandeered several Japanese airliners in the 1970s, and three of its members staged an attack at Tel Aviv’s Lod Airport that killed 26 people in 1972. Militant members of Chukaku-ha — which means “Middle Core Faction” — used a flame thrower to set fire to the ruling Liberal Democratic Party’s Tokyo headquarters in 1984. They fired mortars at Tokyo’s Haneda airport a year later and launched home-made missiles against the Imperial Palace and U.S. Embassy during a meeting of the leaders of the Group of Seven industrial nations in 1997.

The gnomic guru of Japan’s Aum Shinrikyo doomsday cult, former street-corner preacher Shoko Asahara, was obsessed with acquiring an atomic weapon, and his followers traveled to Russia to buy them and recruit former Soviet weapons scientists. Investigators have reported that the group was prepared to pay as much as $15 million for a warhead. In 1993, the group bought a half-a-million-acre sheep ranch in Australia, where 25 of Asahara’s followers tried to mine uranium to fuel a bomb.

When those schemes failed, Asahara turned to home-brewed biological and chemical weapons, ultimately ordering a sarin nerve gas attack on the Tokyo subway system in 1995 that killed 13 people and injured 6,000 others. He is currently in prison awaiting execution.

Even after the arrest of its leadership, remnants of Aum studied Japan’s nuclear industry. Tokyo police in March 2000 said Aum-affiliated hackers had obtained schedules of nuclear fuel deliveries, studied the cooling system at Japan’s plutonium-fueled Monju prototype fast breeder reactor, and built dossiers on 75 Japanese researchers doing nuclear-related work.

A July 2011 report by Richard Danzig, former Navy secretary and a current member of President Obama’s four-member Intelligence Advisory Board, found that “police pursuit of Aum was remarkably lax.” The cult was shielded from close scrutiny by Japanese privacy and religious-freedom protections, as well as a conviction by authorities that it was a collection of harmless cranks.

Terrorist Khalid Sheikh Mohammed, who was captured in May 2003, told interrogators that he had tried to recruit hijackers to seize an airliner at Tokyo’s Narita airport and crash it into the U.S. Embassy in the center of the crowded city. Because of restrictions on sharing classified information with Japan, Schieffer said, he wasn’t able to tell Japanese officials that Tokyo had been a target of Al Qaeda for years, until Mohammed’s confession became public in March 2007.

“It upset the Japanese greatly when they found out about it,” he said.

For years, however, Japan resisted taking steps that would have made it possible to share classified information with the United States about nuclear threats, partly out of concern that doing so might weaken public support for nuclear power, according to another U.S. diplomatic cable published by Wikileaks.

Yasuyoshi Komizo, a nonproliferation official in Japan’s Ministry of Foreign Affairs, told a delegation from the U.S. Department of Energy in 2008 the government worried that “if, for example, the information sharing concerned potential insider threats, that could be interpreted as suggesting that some segment of the Japanese population was a problem,” the cable quoted him as saying.

A law giving the government sweeping powers to classify information was passed at the insistence of Prime Minister Shinzo Abe in December last year. But it hasn’t quelled U.S. concerns.

For a decade the United States has urged Japan “in a friendly way, in a nonthreatening way, to elevate their understanding of the threat,” said the senior Obama administration official. “Do they have the weapons and defensive systems that we have at nuclear facilities? Almost certainly not,” the official said. Instead, Japan has treated the security of their nuclear facilities — all of them civilian — as more of a law-enforcement task than a quasi-military mission.

“History so far hasn’t proven them wrong,” the official said. “But you have to ask, what level of risk are you willing to accept?” The closer Rokkasho is opening, the more urgent the question becomes.

A prime tourist destination

Roughly 100,000 Japanese a year come to the olive-green, futuristic visitors center on a hillside overlooking the country’s new plutonium production plant, just one part of a massive nuclear tourist trade nurtured by the government and industry to assure Japanese the technology is safe. There, visitors gaze down from a second-floor window at a vast fairy-tale city, a nuclear Oz rising from the Pacific headlands, with towers that resemble minarets and 20 or so turquoise-striped, steel-sided structures that look like children’s building blocks.

The plant, spread over a square mile of scraped earth at the edge of the ocean, is entered at a gate guarded by an elderly man with a blue uniform and gloves, who bows as he accepts passports from visitors. Stark and surprisingly barren during a twisting van ride late last year along its broad asphalt roads, the facility is surrounded by a maze of fences and multiple layers of electronic security, including what its officials said were up to three rings of intrusion detectors. A small contingent of armed police is stationed in an office within the outer gates of the huge complex, but none are within the plutonium processing facility.

At the entrance to each building where radioactive materials are kept, unarmed guards issue badges and direct visitors through radiation sensors. If the guards and the police are outmanned or outgunned, plant officials said, they can summon other forces from elsewhere, officials said. But the first line of defense is the unarmed security force.

Nuclear engineer Tomonori Iwamoto, who worked as a United Nations weapons inspector in Iraq and serves as director of Rokkasho’s Nuclear Security and Safeguards Division, said while escorting two reporters around the facility that the most sensitive structures have thickly-reinforced concrete roofs to protect them against an attack from the sky. A nearby United States Air Force base, at Misawa, has a Patriot anti-missile battery, he noted.

But the perimeter control system hasn’t always worked as designed. A Japan Nuclear Fuel Ltd. internal report details an Aug. 7, 2009, incident in which security guards allowed a group of construction workers to enter a storage facility for lethally radioactive, high-level wastes, without proper authorization. There were two prosaic problems, according to the report, which was obtained by the Center for Public Integrity. One was “a lot of debating and chatter” at the guard’s desk as the workers waited to enter; another was a failure of the plant’s computer system for checking IDs that day.

Plant critics have noted that a similar perimeter security system did not work at the Fukushima complex in March 2011, when a political activist crashed a truck fitted with a loudspeaker through a gate and stopped within 100 feet of one of the shuttered reactors there. He wasn’t arrested until the next day. Police did the only thing they could do under Japanese law: They charged him with trespass, a lesser allegation than Americans could make in a similar circumstance.

At Rokkasho, parts of the plant are already highly radioactive and formally off-limits due to its production of 4.3 tons of plutonium from spent nuclear fuel in test runs that began in 2006. Iwamoto led visitors through a five-inch thick, remotely controlled steel door to an observation area above the control room where, during operations, about 80 employees work. The observation deck and control room are separated by bulletproof glass.

When production is in full swing, ships carry huge cylinder-shaped, radiation-shielded shipping containers or “casks” to Rokkasho’s seaport. From there, special squat blue trucks trundle the casks — each carrying 13-foot high bundles of fuel rods composed of irradiated uranium pellets — up to the plant along a two-mile, restricted road. The casks are unloaded automatically in a warehouse-sized storage facility and lifted into 39-foot-deep cooling ponds. Remotely operated machines open them underwater.

The spent fuel is kept immersed until it is processed, to blunt its intense radiation, which for the first 100 years can kill outright about half of adults foolish enough to loiter nearby for more than three or four hours. A robotic crane removes the bundles from the pool and feeds them into a huge wedge-shaped device that slides back and forth like a deli slicer, carving thin layers off the ends.

The metal chips are funneled into a vat of nitric acid where the chips are dissolved into a lethal broth containing about 96 percent uranium and one percent plutonium, plus dozens of other highly radioactive elements.

Pumps push the heavy liquid through vertical tanks, where the plutonium and uranium are separated through a series of chemical treatments. The cocktail of high-level liquid waste, which can reach temperatures over 1,100 degrees Fahrenheit, is siphoned off into a large, refrigerated underground tank, where it will later be mixed with molten glass and formed into log-shaped cylinders for storage.

Finally, some of the uranium is remixed with equal parts plutonium and the compound is dried to form a yellow-green oxide the consistency of flour. The purpose of creating the mixture is to ensure that the plutonium can’t be directly used to build a bomb.

The problem is that plutonium has some unsettling properties: It tends to smear, smudge and creep into crevices, where it sticks like lampblack. When chopped up, grains can slip into cracks and corners. When dissolved in acid, it can coat pipes or cling to chemical wastes. Small amounts can stick to scrap metal when equipment is replaced.

That’s why experts say the International Atomic Energy Agency will be able to track only 99 percent of the plutonium as it moves through the plant, even with a comprehensive monitoring plan based in part on a computerized, three-dimensional map derived from laser range finding. “That’s the best we can do with measurement,” said Shirley Johnson, a chemist and retired IAEA safeguards inspector, who has worked at Rokkasho.

While 99 percent might sound good, the plant’s annual output will be so high that a one-percent error rate means roughly eighty kilograms of plutonium a year could be untraceable — enough for 26 bombs. Critics worry as a result that the large uncertainties will open the door to diversion attempts by insiders.

Asked for comment, Gill Tudor, an IAEA spokeswoman in Vienna, did not dispute the one percent error estimate, which experts say is standard for all such large plants. But she said “nuclear material accountancy is only one of the safeguards measures” that will be applied to Rokkasho, and that the agency will for example also make random, short-notice visits to monitor the plant’s operation. She added that all the measures “provide assurance that all nuclear material remains in peaceful purposes at the Rokkasho plant.”

The plants operators say that many of the operations will be done robotically or by remote control, and under the gaze of 65 overhead and underwater video cameras watched at IAEA headquarters in Vienna. To guard against sabotage, Iwamoto said that the plant was preparing to institute a rule requiring two persons to participate in the most sensitive operations.

But none of the workers have been subjected to formal background checks like those required for anyone given access to secure areas at U.S. nuclear plants, including part-time workers. Those checks typically involve verification of a worker’s identity, confirmation of past employment, a search of FBI records based on fingerprints, a drug test, a credit check and reports from references.

Employers in Japan, in contrast, are barred from accessing government records to verify whatever workers claim, and part-time contractors are often not vetted at all.

As the tour ended, Kaoru Yoshida, the silver-haired director of media relations for Japan Nuclear Fuel Ltd., the utility that will operate the plant, invited a journalist to sit with him in a small café at the plant so he could quell anxieties by setting the record straight. He is well-known to Japanese media as the combative chief spokesman for the Tokyo Electric Power Company during the early months of the Fukushima crisis.

The Rokkasho plant, Yoshida said, was built strictly as part of Japan’s civilian energy program, not to serve any potential nuclear arms program. Nor, he said, was there any chance that workers at the plant would try to pilfer any plutonium. “We think we have a 100 percent guarantee that the people working here would not do that,” he said.

As for terrorism, he said, why would militants target the plant? Rokkasho’s mixture of plutonium and waste uranium can’t be used to make a bomb. “Because the plutonium is mixed already with uranium, because of the security level that we have here, we don’t have plutonium itself,” he said. “It doesn’t exist here.”

But independent experts say mixing the two nuclear materials does little to reduce the plutonium oxide’s potential to become a bomb fuel.

Paul Dickman, the former NRC official, is a chemist and a policy fellow at the Department of Energy’s Argonne National Laboratory, the premier center for U.S. research into fast breeder reactors. He said the only difference between uranium-plutonium oxide and the pure metallic plutonium preferred by bomb-builders “is a chemist.” Extracting the plutonium from the mixture would not be difficult, he said. “It doesn’t take much to do the separation.”

A difference of opinion inside Japan

Nobumasa Sugimoto, director of nuclear security at the government’s new Nuclear Regulation Authority— a group established in part to implement tougher rules in the aftermath of the Fukushima disaster — offered a less sanguine view than Yoshida of the risks at Rokkasho.

Speaking about potential terror attacks on nuclear facilities, Sugimoto said “we believe that these incidents could occur at any time.” He spoke while surrounded by boxes and little furniture at the authority’s Tokyo office, a year after its creation.

He said that his new group is particularly concerned about reports that companies with links to organized crime are providing services to the nuclear industry. Hundreds of subcontractors, for example, are working on the government-sponsored cleanup of radioactive fallout in the zone around the devastated Fukushima reactors. Police say some are linked to the yakuza, tattooed mobsters who operate in a kind of twilight zone, engaging in legitimate businesses as well as loan-sharking, extortion and other crimes.

The authority is concerned, Sugimoto said, that if yakuza-connected workers are given sensitive jobs, they could be bribed into conspiring with terrorists to steal materials or mount an attack. “Basically, they are criminals, and they would do anything for money,” he said. A senior official at the National Police Agency, speaking on condition of anonymity to discuss sensitive government information, confirmed that the yakuza have been involved in nuclear site operations.

The regulatory group’s experts will publish a report later this spring recommending tighter security measures, including some form of background checks for workers, he said. He called these regulations “one thing we definitely lack.”

But he added that there is little chance of arming the private security guards at Rokkasho or other nuclear plants. “It’s a very strong and deeply cultural way of thinking, and therefore civilians, although they are security guards, are requested to do their jobs unarmed,” he said. “If arms would be given to security guards, there would be a huge national debate.”

What if unarmed guards like those at Rokkasho were confronted by armed terrorists? Sugimoto said they are trained to call the police. “The security guards are expected to withdraw for their lives if there is a lethal threat,” he said, echoing remarks made by other Japanese officials to U.S. officials, who recall being astonished.

Japan’s prime minister during the Fukushima disaster in 2011, Naoto Kan, said in an interview with the Center at his parliamentary office that he worries that Japan’s government and industry are still committed to propping up the plutonium program, despite what he now claims are some obvious reasons to cancel it.

Kan, a member of the opposition Democratic Party of Japan, is one of several ex-premiers urging the conservative Abe government to reconsider its commitment to nuclear power — so far without success. Before the disaster, Kan said, he had debriefed some officials with the Nuclear and Industrial Safety Agency who had traveled to the U.S. to discuss the terror threat to nuclear plants. NISA, since abolished, was part of the powerful, Ministry of Economy, Trade and Industry, a bastion of support for the nuclear industry.

Kan said the NISA officials returned from their trip unimpressed, telling him they concluded that “America might be under terrorist attacks, but Japan is very unlikely to be so.” Therefore, Kan said, NISA felt it wasn’t necessary to take the threat of terror attacks on nuclear facilities seriously.

He said this attitude was widely shared in industry and government. “Japan simply didn’t consider terrorism a possibility here,” he said, and as a result “Japan almost entirely ignored the advice” of the United States after 9/11.

“And you may ask whether Japan is prepared for such threats. Well, the answer is that it isn’t prepared for such attacks.”

Toshihiro Okuyama and Yumi Nakayama, staff writers for the Japanese newspaper Asahi Shimbun, contributed reporting for this article.