History

In 1954, Japan budgeted 230 million yen for nuclear energy, marking the beginning of the program. The Atomic Energy Basic Law limited activities to only peaceful purposes.
The first nuclear reactor in Japan was built by the UK's GEC. In the 1970s the first Light Water Reactors were built in cooperation with American companies. These plants were bought from U.S. vendors such as General Electric or Westinghouse with contractual work done by Japanese companies, who would later get a license themselves to build similar plant designs. Developments in nuclear power since that time has seen contributions from Japanese companies and research institutes on the same level as the other big users of nuclear power.
Robert Jay Lifton has asked how Japan, after its experience with the atomic bombings of Hiroshima and Nagasaki, could "allow itself to draw so heavily on the same nuclear technology for the manufacture of about a third of its energy". He says:
There was resistance, much of it from Hiroshima and Nagasaki survivors. But there was also a pattern of denial, cover-up and cozy bureaucratic collusion between industry and government, the last especially notorious in Japan but by no means limited to that country. Even then, pro-nuclear power forces could prevail only by managing to instill in the minds of Japanese people a dichotomy between the physics of nuclear power and that of nuclear weapons, an illusory distinction made not only in Japan but throughout the world.
Japan's nuclear industry was not hit as hard by the effects of the Three Mile Island accident (TMI) or the Chernobyl disaster as some other countries. Construction of new plants continued to be strong through the 1980s, 1990s, and up to the present day. However, starting in the mid-1990s there were several nuclear related accidents and cover-ups in Japan that eroded public perception of the industry, resulting in protests and resistance to new plants. These accidents included the Tokaimura nuclear accident, the Mihama steam explosion, cover-ups after an accidents at the Monju reactor, among others, more recently the Chūetsu offshore earthquake aftermath. While exact details may be in dispute, it is clear that the safety culture in Japan's nuclear industry has come under greater scrutiny.

Canceled plant orders include:

• The Maki NPP at Maki, Niigata (Kambara)—Canceled in 2003
• The Kushima NPP at Kushima, Miyazaki—1997
• The Ashihama NPP at Ashihama, Mie—2000
• The Hōhoku NPP at Hōhoku, Yamaguchi—1994
• The Suzu NPP at Suzu, Ishikawa—2003
Note that the Suzu NPP plant proposal is said to be "frozen", meaning that it may continue sometime in the future if economic factors turn more in its favor, though there has been no sign of this happening.

These cancellations reflect to some degree the safety concerns that surfaced after the Monju cover-up (1995) and the Tokaimura accident (1999) and could be compared to the situation in the United States where there was a large number of plant order cancellations after TMI and the Chernobyl disaster. However, it is important to note that most cancellations in Japan are a result of 10, 15, or more years of postponed work and poor support. Through the same time period there were also some new plants connected to the grid, and as of 2007, construction is in progress on several other plants. Japan has thus yet to see a complete break in the construction of new nuclear plants, which has happened in the United States and France.
The Japanese government has maintained strong support for nuclear power. After the Tokaimura accident, many reorganizations of the government funded research organizations occurred and stricter controls were enforced, but the size and scope of research in nuclear power topics has continued to expand. While the number of reactors is expected to increase, the focus of new developments will shift to the advanced fuel cycle and next generation plants. Japan plans to be a major player in the Global Nuclear Energy Partnership and has joined the ITER project. Furthermore, a United States-Japan Joint Nuclear Energy Action Plan has also been created, which is indicative of the commitment the Japanese government has to new nuclear technologies.
In March 2008, Tokyo Electric Power Company announced that the start of operation of four new nuclear power reactors would be postponed by one year due to the incorporation of new earthquake resistance assessments. Units 7 and 8 of the Fukushima Daiichi plant would now enter commercial operation on October 2014 and October 2015, respectively. Unit 1 of the Higashidori plant is now scheduled to begin operating in December 2015, while unit 2 will start up in 2018 at the earliest.
As of September 2008, Japanese ministries and agencies were seeking an increase in the 2009 budget by 6%. The total requested comes to 491.4 billion Japanese yen (4.6 billion USD), and the focuses of research are development of the fast breeder reactor cycle, next-generation light water reactors, the Iter project, and seismic safety.

International cooperation

The nuclear industry in Japan has been highly affected by its U.S. counterpart. Through the late 1990s to present day, the industry has become confident that the United States would see construction of new nuclear plants. Hoping to take advantage of that, along with other opening markets, joint venture agreements between the major nuclear fuel vendors occurred in 1999, 2006, and 2007, following from the legacy of co-operation that began when Japan imported Western technology to jump start its nuclear fleet.
On April 18, 2007, Japan and the United States signed the United States-Japan Joint Nuclear Energy Action Plan, aimed at putting in place a framework for the joint research and development of nuclear energy technology. Each country will conduct research into fast reactor technology, fuel cycle technology, advanced computer simulation and modeling, small and medium reactors, safeguards and physical protection; and nuclear waste management.