Hiroshima bomb
Japan is the only country ever to be attacked with a nuclear weapons (See Hiroshima, World War II). Today Japan is protected from nearby countries with nuclear weapons’such as China, Russia and North Korea — by the U.S. Nuclear umbrella.

In 1967, Japan declared for the first time what is now known as the “three non-nuclear principals”: “do not use, possess or allow nuclear weapons into the country.” Despite this, in 1969, according to a Japanese government report released in November 2010, Japan discussed the possibility of obtaining nuclear weapons in cooperation with West Germany.

In 1971, the Japanese parliament overwhelmingly voted to add the three non-nuclear principles — never to own, produce or allow nuclear weapons on Japanese soil — to the Japanese constitution. A Japan-sponsored resolution to eliminate nuclear weapons was adopted by the United Nations in 2007 by a vote of 165 in favor and three against and 19 abstentions, Those who voted against it were the United States, North Korea and India. In 2010, for the 17th time, Japanese submitted a resolution to the United nations calling for the elimination of nuclear weapons.

Some conservative politicians even would like to see Japan develop its own nuclear weapons. In October 1999, deputy defense minister Shingo Nishimura resigned after expressing that view. By the early 2000s, with an increasing threat from North Korea, the view was not perceived as so extreme. The Chinese and other worry that North Korea’s detonation of a nuclear device will give Japan an excuse to develop its own nuclear weapon.

It is widely assumed that Japan can develop nuclear weapons within a year at any time. A member of the Manhattan project who visited Japan in 1950s said then that Japan had the technology to develop nuclear weapons in five years and that was more than 50 years ago. At the end of 2005, Japan possessed 43.8 tons of plutonium, of which 5.9 tons — enough to make 700 nuclear bombs — was stored domestically. This plutonium however is not weapons grade (weapons garde plutonium is 90 percent pure) and weapons grade plutonium is difficult to produce but is possible using the light water reactors that Japan possesses. To produce weapons grade plutonium efficiently it needs a graphite moderated reactor — which it doesn’t have.

A computer simulation has showed that if a nuclear bomb, about 10 times more powerful than the one that hit Hiroshima, were to strike Tokyo today more than 2 million people would die immediately and another million would be exposed to very high levels of radiation and 1.7 million would lose their eyesight and hearing and suffer respiratory disorders.

History of Nuclear Weapons in Japan After Hiroshima

Evan Osnos wrote in The New Yorker: The story of how Japan became one of the world’s most devoted, and improbable, advocates of nuclear technology begins in August, 1945. In the days immediately after the United States dropped atomic bombs on Hiroshima and Nagasaki, radiation was largely a mystery to the Japanese public; men and women had survived the explosion but were succumbing to a new illness — an “evil spirit,” as a national newspaper put it. [Source: Evan Osnos, The New Yorker, October 17, 2011]

Nine years later, Japan had another encounter with nuclear technology: on March 1, 1954, the U.S. tested what was the world’s most powerful hydrogen bomb on Bikini Atoll, in the Pacific. The blast was more than twice the size that engineers had predicted, and a shower of radioactive ash reached far enough to envelop a voyaging Japanese tuna boat named the Lucky Dragon No. 5. The twenty-three crew members had no idea what had dusted them. ‘I took a lick; it was gritty but had no taste,” one wrote later — but by the time they returned to shore they were burned, blistered, and in the early stages of acute radiation sickness. Their contaminated tuna was sold at the market before anyone stopped it.

The ordeal caused a panic in Japan; a petition against further hydrogen-bomb tests secured the signature of one in every three citizens. It was the start of what became known as Japan’s “nuclear allergy.” In less than a year, Japanese filmmakers had released “Godzilla,” about a creature mutated by American atomic weapons. “Mankind had created the Bomb,” the film’s producer, Tomoyuki Tanaka, said of his monster, “and now nature was going to take revenge.” Godzilla’s radioactive breath and low-budget special effects were campy to the rest of the world but not to the Japanese, who watched the film in silence and left theatres in tears.

As the Cold War progressed, President Eisenhower fretted that the nuclear allergy could drive Japan out of America’s embrace. Ever since the Lucky Dragon incident, America had been portrayed as a nation of “skunks, saber-rattlers, and warmongers,” he complained in a meeting with the National Security Council. In a secret memo, the Acting Secretary of State told him, “The Japanese are pathologically sensitive about nuclear weapons. They feel they are the chosen victims.” He advised the President to apologize and compensate the fishing crew, but added that the best remedy for the Japanese people’s “emotion and ignorance” about the atomic age was to pull them into it — by building them a reactor. Eisenhower had recently announced the Atoms for Peace plan, to spread civilian nuclear technology to allies around the world. Representative Sidney Yates, of Illinois, proposed that an ideal place for Japan’s first plant would be Hiroshima itself — to “make the atom an instrument for kilowatts rather than killing.”

As it turned out, America’s emerging priorities coincided with Japan’s.After the Japanese surrender, in 1945, General Tomoyuki Yamashita was asked why his country had lost the war. He answered, “Science.” The triumph of American weaponry had convinced a generation of Japanese élites that their country must reëngage the world on the basis of trade and technology. But Japan’s islands were chronically short of coal and oil — the war had been partly a hunt for energy — and, as the country embarked on its economic growth spurt, it was desperate for new sources of electricity.

Japan’s Effort to Build a Nuclear Bomb

Japan along with Germany, Italy, Switzerland, Canada, South Korea and Taiwan are all believed to have conducted some nuclear weapons research during the Cold War period. Japan reportedly has the largest stock of weapons-usable plutonium aside from states that already have nuclear weapons. Many people believe that Japan has the technology to easily develop nuclear weapons if it wants to. It also has rockets and missiles that can easily be adapted to carry nuclear weapons.

Martin Fackler wrote in the New York Times, “In 1945, in the closing months of World War II, the Japanese imperial army’s attempted to mine uranium and develop ways of refining it for use in building a bomb. Compared with the United States’ vast Manhattan Project, historians describe Japan’s two bomb-building programs — the imperial navy also ran a separate project — as minuscule, last-ditch efforts, hindered by a lack of resources and pessimism among the projects’ own scientists that such a weapon could actually be completed. [Source: Martin Fackler, New York Times, September 5, 2011]

Historians say Japan never got as far as even designing, much less actually building, an atomic weapon. Indeed, its wartime efforts can seem woefully insufficient for the task. To obtain uranium about 130 schoolchildren were put to work digging for uranium ore in Ishikawa — ironically bear the Fukushima nuclear power plant — because the adult men had all been sent off to war.

Kiwamu Ariga, who turned 81 in 2011, participated in digging the uranium ore, told the New York Times that he and his classmates were put to work hacking rocks out of the hill’s then exposed stone face until the blood ran from their sandaled feet. The soldiers told them nothing beyond instructing them to look for stones with brown or black spots.

Then one day, Mr. Ariga recalled, an officer finally explained what they were after: “With the stones that you boys are digging up, we can make a bomb the size of a matchbox that will destroy all of New York.” Mr. Ariga said he did not learn other details of Japan’s secrecy-wrapped efforts to build an atomic bomb until years after the war. “We had no idea what we were doing here, in our bare feet, digging out radioactive uranium,” Ariga said.

The programs were revealed soon after the war but was not talked about much as an economically resurgent Japan tried its best to put its wartime past behind it. Since the 1990s, major media have become less inhibited about discussing the war, including Japan’s atomic bomb programs. However, the programs still seem to be easily forgotten in a nation that is more accustomed to thinking of itself as the victim of the deadly American atomic attacks on Hiroshima and Nagasaki. Ariga, who in recent years has begun telling his story to local schoolchildren, says that most Japanese are shocked to hear that their nation also tried to build an atomic bomb. “I have no doubt Japan would have used it if it succeeded,” he added.

Japan’s Crippled Defense Industry and Arms Exports

On the impact of Japan’s arms export ban and restrictions on Japan’s defense industry, Yomiuri Shimbun reported: “An enormous amount of time and money is needed to develop technology to improve the capability of fighter jets, missiles and other military equipment. This has encouraged an increasing number of countries to cooperate with other nations in developing weapons. However, Japan's three self-imposed principles do not allow it to join forces with other nations to develop weapons. There are concerns that if the three principles are not relaxed, Japanese weapons manufacturers will be unable to keep pace with the technology being developed overseas. [Source: Yomiuri Shimbun, November 1, 2011]

In an editorial the Yomiuri Shimbun said: It is “of grave significance that many defense-related industries have stopped making defense equipment because of falling sales. If experts in defense equipment production drop precipitously, it will become extremely difficult to recover human resources, threatening the very basis of production and technological competence in the defense industry. [Source: Yomiuri Shimbun, October 8, 2011]

The government is also paying more to purchase the F-35 stealth jets than other countries, as Japan's long-standing weapons export ban prohibiting participation in joint arms development projects with other nations, has prevented Tokyo from taking part in the F-35's development. "Considering Japan's fiscal crisis, it would be better for the government to change the ban on exporting weapons so that it can jointly develop military aircraft at a lower cost," Michishita said."The government should make efforts to reduce the cost as much as possible.”

Japan’s Arms Export Ban

Japan has had a ban on arms exports since the 1960s when it adopted the three principles, which refer to the Japanese government's policy of not handing over, or exporting, weapons and weapons-producing technology to any other nation. According to the Yomiuri Shimbun: “In 1967, then Prime Minister Eisaku Sato told a Diet session that Japan would not export weapons and related technology to three types of nations--communist block countries such as the Soviet Union (now Russia); nations designated by the United Nations as subject to an arms export ban; and countries at war or engaged in other armed hostilities. These rules cited by Sato have since been referred to as the three arms export principles. [Source: Yomiuri Shimbun , October 1, 2011]

In February 1976, the administration of then Prime Minister Takeo Miki produced a "unified government view," saying that Japan should "refrain from" exporting weapons even to countries that were not subject to the 1967 principles, thus imposing a nearly total ban on arms exports. There have been exceptions, however, beginning with the provision of weapons and related technology to the United States in 1983, and the more recent Japan-U.S. development and production of missile shields under a ballistic missile defense program. [Source: Yomiuri Shimbun, December 28, 2011]

The constraints of the ban have meant the nation's defense industry has been unable to take part in international projects to develop and produce military equipment. Critics of the ban have warned of a decline in Japan's defense technological capabilities and of rising costs to obtain the latest military equipment, such as fighter jets. The arms export ban has also kept the Self-Defense Forces from donating equipment such as helmets and protective vests after completing their U.N.-sponsored peacekeeping operations. Analysts have been saying for years that this kind of provision should not be banned.

Japan Eases Arms Export Ban

In December 2012, the Yomiuri Shimbun reported: “The government has officially decided to drastically revise the nation's so-called three principles on arms exports, which would make it possible for Japan to participate in the development and production of military equipment with other countries, Chief Cabinet Secretary Osamu Fujimura said. Fujimura read the statement on the decision to establish new rules that would relax the longstanding effective ban on arms exports. The new guidelines are called "criteria regarding overseas transfers of defense equipment." [Source: Yomiuri Shimbun, December 28, 2011]

The new criteria comprise two key elements: 1) Japan may participate in joint projects to develop and produce military equipment and technology with other countries, such as the United States and European nations. 2) Japan may export defense-related equipment to support peace-building or humanitarian objectives.

The changes announced mark the first significant alteration to the blanket ban since it was introduced in 1976. The government's statement said the new rules require "strict administrative procedures" that will ensure defense equipment from Japan will not be used for purposes other than those approved by the government, or transferred to third-party nations without Japan's consent. Further, the statement said Japan could join international projects for developing and producing weapons if the other participating nations have "cooperative security relations" with this nation, and also when the projects would enhance national security.

Yukiko Ishikawa wrote in the Yomiuri Shimbun: “The F-35 that Japan has decided to employ as its next-generation fighter jet was developed through the cooperation of nine countries, including the United States and Britain. Japan was asked to join the development project, but Tokyo was unable to do so because of the rules on weapons exports. Easing the rules would make it possible for Japan's defense industry to take part in similar international projects to develop and produce military equipment and technology. Additionally, the government is eyeing the export of Japan-made defense equipment parts in the future, the sources said. [Source: December 28, 2011]

Domestic Firms to Make F-35 Parts from 2017

In November 2012, The Yomiuri Shimbun reported: “The government plans to allow domestic companies to start manufacturing in fiscal 2017 parts for the F-35 stealth jet, which will be introduced by the Air Self-Defense Force in fiscal 2016. It will be the first time Japanese firms can take part in such manufacturing, as the joint development or manufacturing of defense equipment with other countries, including the United States and European nations, was not possible under Japan's long-standing three principles on arms exports., which was relaxed in December 2011. [Source: Yomiuri Shimbun, November 9, 2012]

Japanese businesses' participation in the manufacturing of F-35 parts is expected to help maintain and enhance such domestic capabilities. It is expected to create a positive economic impact too, as there are many aviation-related businesses in the country. During the selection process for the F-35 jet as the next frontline fighter in the ASDF's arsenal, Japan agreed with the United States in December that Japanese companies would manufacture up to about 40 percent of the parts used in assembling F-35s should they participate.

Specifically, Japanese firms are in line to manufacture F-35 body parts, including main wings, tails and avionics information processing systems. The F-35, a fifth-generation fighter jointly developed by the United States, Britain and seven other countries, has advanced enemy sensors and high stealth capabilities, making it difficult to detect with radar. It also has advanced communications network capabilities enabling F-35 pilots to share information gathered from Aegis-equipped vessels and ground radars.

Japanese Spies

Japan has traditionally relied on the United States for intelligence. The Foreign Ministry, the Defense Agency, the Cabinet Information Research Agency, National Police Agency and Public Security Investigation Agency all collect and analyze intelligence.

In December 2006, the Japanese military announced its intention to establish a “central intelligence unit” called the “Overseas Intelligence Corps.” In October 2005, discussion began on setting up an MI-6-type spy agency in Japan.

In January 2008, an official at the Cabinet Information Office was fired for passing classified documents to the Russian Embassy for money. In January 2007, a Japanese engineer and his wife were arrested on charges of passing on military secrets to the North Koreans.

In December 2007, a 34-year-old Maritime Self-Defense Force lieutenant commander was arrested on suspicion of passing top secret information about American Aegis destroyer to another commander, Japanese military personnel working with American military technology are not supposed to reveal classified information about this technology. The officer pleaded not guilty, admitting that he passed information while arguing he failed to break any law.

Selling Technology and Secrets in Japan

Japan has a de facto ban on arms exports that was set up in 1967 to prohibit arms deals with communist states and states involved in international military conflicts. Many feel its time for the ban to go, arguing that ending the ban could help generate revenues for the defense industry and preven its technology from becoming out of date. Ending the ban would also allow Japan to join joint projects that could improve its military capabilities and save it money.

Five executives at Sinshen Enterpises, a Tokyo-based engineering machinery company, were arrested for selling jet mills and other sophisticated machinery than can be used to make missile parts to Iran and North Korea.

In August 2006, an employee at a trading form was charged for illegally exporting to North Korea a freeze dryer that can be used make biological weapons.

In August 2006, a former Nikon researcher was accused of stealing a device with military applications — a variable optical attenuator (VOA), which intensifies light passing through fiber opticcables, allowing transmissions of large amounts of data — and selling it to the Russians. The researcher also sold infrared technology which can be used to more accurately target missiles.

In 2005, an employees at a subsidiary for Toshiba was charged with selling sensitive technology to spies. In 1987, Toshiba got in trouble for selling technology to the Soviet Union that could be used to make sophisticated submarine parts.

In August 2006, the president of a leading precision tool company, Mitutoyo, was arrested for illegally selling two 3-D measuring devises — used in centrifuges for refining uranium for nuclear weapons — that were found in a shipment to a nuclear facility for Libya.

In January 2006, it was revealed that Yamaha illegally sold remote-controlled helicopter that could used for military purposes to the Chinese army.

Chinese Spy Steals Classified Rice Data in Japan

In June 2012, a Chinese diplomat accused of engaged in espionage in Japan was investigated for using a false identity to obtain a foreign resident card in the first case of a Chinese diplomat being subject to a criminal investigation by Japanese police. The diplomat — Li Chunguang, a first secretary of the Chinese Embassy in Tokyo — Li was not formally indicted as he left Japan to "temporarily return home" just after being asked by the MPD to appear for questioning. [Source: Yomiuri Shimbun, June 2, 2012]

The Yomiuri Shimbun reported: “Li is believed to have approached Japanese firms under the pretext of helping them expand their operations in China. His aim, in addition to private gain, was apparently to put the companies under the influence of China's People's Liberation Army, and make them a source of revenue, the sources said. According to a statement by Tokyo police Li is suspected of having renewed his alien registration card using a false address, and falsely identifying himself as a University of Tokyo researcher, in his application to Tokyo's Katsushika Ward government office on April 10, 2008.

In August 2009, Li told the Tokyo Regional Immigration Bureau that he was an employee of a Tokyo trading company and tried to renew his visa status as a researcher. However, the attempt failed, as an immigration officer discovered he was a Chinese diplomat. In January 2008, Li opened multiple bank accounts by fraudulently using the alien registration card obtained while he was a university researcher, even though he had already become a Chinese diplomat at that time, the investigative sources said.

Investigators discovered that from February to July 2008, 70,000 yen to 160,000 yen a month was wired into one of Li's bank accounts by a Tokyo-based health food marketing company as "advisory fees." After the health food company established a branch in Hong Kong, it transferred 720,000 yen to one of the diplomat's accounts in June 2009, the sources said.

Li is suspected of having obtained information that can influence rice market prices and the ministry's internal rules regarding cables, among confidential Agriculture, Forestry and Fisheries Ministry documents related to a program led by Senior Vice Agriculture, Forestry and Fisheries Minister Nobutaka Tsutsui. The documents in question were initially obtained by the head of the Promotion Association of Agriculture, Forestry, Fisheries & Foods Exporting to China. The association head, a former state-funded secretary of a House of Representatives member, also served as an adviser to the ministry before assuming the current post. [Source: Yomiuri Shimbun, June 4, 2012]

The Yomiuri Shimbun confirmed that the leaked documents were those the association head obtained after resigning as ministry adviser. These documents included five classified as "level 3" and five as "level 2," the highest and second-highest confidentiality levels, respectively, in the ministry's three-grade scale. In one document titled "Future prospects of rice supply and demand," it was said that about 100,000 tons of rice grown in Fukushima Prefecture could face circulation problems due to the crisis at the Fukushima No. 1 nuclear power plant. It also said shipments of rice produced in 2011 could decline because of expectations of a rise in prices. A senior ministry official pointed out the high confidentiality level of the documents, saying the ministry's rice price forecasts, if leaked, would greatly affect retail prices, as rice is handled in futures trading, too.

Military Accidents in Japan

In July 1988, 30 people were killed when a an MSDF submarine collided with a leisure boat full of sport fishermen off Yokosuka Port in Kanagawa Prefecture.

In November 2006, a Japanese submarine collided with a chemical tanker while surfacing during exercises off the coats of Kyushu. No one was killed or injured but both vessels were damaged,

In January 2006, a U.S., nuclear sub collided with a Japanese tanker in the Persian Gulf. There no reports of oil leakages, injuries or radiation releases.

In October 2009, a Japanese destroyer collided with a South Korean container ship in the Kanmon Strait between Kyushu and Honshu. The container ship veered into the path of the destroyer as it tried to pass another vessel in one of the narrowest and trickiest parts of the tricky straight. No one was seriously hurt but there were large fires on both ships and the nose the destroyer, especially, was badly damaged, Some questions were raised about maritime traffic controllers in the area and why the destroyer couldn’t somehow evade the container ship.

Japanese Navy Vessel Collision with Fishing Boat

In February 2008, a collision between an MSDF Aegis-equipped destroyer — the 7,750-ton Atago — and a fishing boat — the 7.3-ton Setoku Maru — in the Pacific Ocean 40 kilometers off of Chiba prefecture left two fishermen dead. The accident occurred at 4:07 am. The fishing boat was cut in two by the destroyer. The bodies of the fishermen were never found.

Reports from the fishermen and the military ships’s crew were quite different. The destroyers crew claim the fishing boat was no using proper lights. Fishermen who survived insist they were.

The crew of the destroyer on duty had just rotated seven minutes before the accident. The fishing boat was on the starboard side of the destroyer which means that according to maritime law the destroyer was obliged to give warning and give way. No warning blasts were sounded which suggests that the destroyer’s crew did not see the fishing boat. There was some evidence the destroyer was on autopilot until one minute before the accident.

The accident was particularly embarrassing because the Atago was equipped with one of the world’s most advanced radar detection systems, capable of monitoring hundreds of targets at one time and aiming weapons at 10 of them. Ten members of the crew were on the bridge at the time of the accident. Two lookouts were stationed on the starboard and port sides of the ship. . The weather was fine. The moon was still out. Some blame was placed on the fishing boat for not taking adequate measure to avoid the Atago as other fishing boat on the area had.

The Atago’s radar picked up the fishing boat and look outs visually saw it but the crew failed to take measures to avoid a collision. There were only three or four crew member in the Atago’s radar center — half th normal number — and they failed to see the fishing boat on the radar. The lookout crew saw the fishing boat with the naked eye 12 minutes before the collision but failed to keep close watch on it as the destroyer neared it. Duty officers failed to take information from the lookouts, pass on the information and take maneuvers to avoid the fishing boat.

The Atago disaster had repercussions that affected the whole government. The Defense Ministry was criticized for holding back information. Prime Minister Fukuda personally apologized to the family of the fishermen. There were calls for the defense minister’s resignation. After a report was issued that charged the military with negligence, the navy chief was dismissed, the defense minister took a two month pay cut and dozens of other defense officials were slapped with penalties.

In May 2011, MSDF men were found not guilt in the ship collision as the court found the fishing boat should have avoided the collision with the destroyers. Prosecutors had charged two officers — lieutenant commander Tomohisa Nagaiwa and chief night-duty officer Keitaro Ushirogata — with professional negigence resulting in death and were seeking two year prison sentences for sailors involved in the Atago collison.

Image Sources: Defence

Text Sources: New York Times, Washington Post, Los Angeles Times, Daily Yomiuri, Times of London, Japan National Tourist Organization (JNTO), National Geographic, The New Yorker, Time, Newsweek, Reuters, AP, Lonely Planet Guides, Compton’s Encyclopedia and various books and other publications.

Last updated January 2013

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