The year 2025 marks the 80th anniversary of the victory of the Chinese People’s War of Resistance Against Japanese Aggression and the World Anti-Fascist War. As a defeated State of World War II and a non-nuclear-weapon State Party to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), Japan is prohibited from developing nuclear weapons. However, in recent years, Japan’s right-wing forces have repeatedly sought to break through the three non-nuclear principles long upheld by successive Japanese governments—namely, not possessing, not producing, and not permitting the introduction of nuclear weapons. Japan’s Prime Minister Sanae Takaichi has been making ambiguous statements about these principles, even hinting at the possibility of abandoning them. She has also stated that the option of introducing nuclear-powered submarines should not be ruled out, while a senior official from the Japanese Prime Minister’s Office brazenly claimed that Japan should possess nuclear weapons. These disturbing developments provoke a high degree of vigilance from the international community.
The expanding nuclear ambitions of Japan’s right-wing forces constitute a dangerous signal of the revival of Japanese militarism, posing a serious threat to global peace. In order to present the international community with a comprehensive and fact-based assessment, and to encourage collective vigilance and concerted efforts to curb any attempt to revive Japanese militarism, safeguard the post-war international order, and uphold the nuclear non-proliferation regime, we have prepared this report, Nuclear Ambitions of Japan’s Right-Wing Forces: A Serious Threat to World Peace, which conveys the views and assessments of Chinese scholars and experts from an academic perspective.
The data, information, and materials cited in this report are drawn entirely from open sources. Despite our best efforts, shortcomings are inevitable, and we welcome readers’ constructive feedback. During the preparation of this report, we received valuable guidance and encouragement from numerous scholars and experts, and we also drew upon research findings from domestic and international think tanks and specialists. We hereby express our sincere appreciation.
China Arms Control and Disarmament Association
China Institute of Nuclear Industry Strategy
January 2026
Japanese Prime Minister Sanae Takaichi has been implying the possibility of quitting the three non-nuclear principles, claiming that Japan has not ruled out the possibility of possessing nuclear submarines. Some senior Japanese officials have even floated the idea of owning nuclear weapons. These dangerous attempts, closely aligned with the inflated ambitions to break free from international order, revive militarism and speed up re-militarization, are by no means isolated incidents or personal view. Rather, they are the result of long-standing, carefully orchestrated efforts by Japan’s right-wing forces, which send an extremely dangerous signal. In the short term, Japan’s right-wing forces seek to revise the three non-nuclear principles in order to open the door to the introduction of nuclear weapons. In the long run, the possibility of Japan pursuing nuclear weapons can not be excluded.
During World War II, Japan secretly engaged in nuclear weapons research and development. Nowadays, Japan has established a complete nuclear fuel cycle and possesses relatively advanced nuclear industrial capabilities, enabling it to produce weapon-grade plutonium through reactor and spent fuel reprocessing technologies and facilities. Japan has produced and accumulated plutonium far in excess of the actual requirements of its civilian nuclear energy program, resulting in a long-standing and severe imbalance between the supply and demand of sensitive nuclear materials. Japan also possesses operational platforms capable of delivering nuclear weapons, as well as the technical foundations for the development of nuclear-powered submarines and aircraft carriers.
The increasingly expanding nuclear ambitions of Japan’s right-wing forces constitute a dangerous signal of the revival of Japanese militarism and pose a grave threat to world peace and stability. Japan must strictly adhere to the three non-nuclear principles and fulfill its nuclear non-proliferation obligations. It must profoundly reflect on its history of aggression and make a clean break with militarism. All peace-loving countries and peoples bear the responsibilities to guard against and thwart any dangerous moves of reviving Japanese militarism, to uphold the outcomes of World War II, to safeguard the non-proliferation regime, and to preserve international peace and security.
I. Japan’s Right-Wing Forces Seek to Revise the Three Non-Nuclear Principles and Even Advocate Possessing Nuclear Weapons
As a defeated State of World War II, Japan was prohibited from maintaining industries “which would enable her to re-arm for war” under the Potsdam Proclamation.Article 9 of the Constitution of Japan further stipulates that Japan “forever renounce war as a sovereign right of the nation”, and “land, sea, and air forces, as well as other war potential, will never be maintained”.Japan’s Atomic Energy Basic Act adopted in 1955 provides that Japan’s “research, development and utilization of nuclear energy is limited to peaceful purposes, is to aim at ensuring safety”. In 1967, then Prime Minister Eisaku Satō first explicitly articulated the three non-nuclear principles—namely not possessing, not producing, and not permitting the introduction of nuclear weapons. In 1971, the House of Representatives adopted a resolution affirming adherence to the three non-nuclear principles, which was subsequently endorsed by the House of Councillors. In 1976, Japan acceded to the NPT as a non-nuclear-weapon State, undertaking not to manufacture or acquire nuclear weapons and not to receive whatsoever transfer of nuclear weapons or control over such weapons.
For a long period of time, successive Japanese governments consistently declared adherence to the three non-nuclear principles in their statements. In recent years, however, Japan’s right-wing forces have repeatedly sought to break through these principles, warranting a high degree of vigilance. In February 2022, former Prime Minister Shinzo Abe floated the idea of Japan “sharing” in the possession of nuclear weapons, as is practiced by some NATO members, in light of the Ukraine crisis and Ukraine’s history of giving up nuclear weapons. Shortly thereafter, then chairperson of the General Council of the Liberal Democratic Party (LDP) Tatsuo Fukuda expressed support for Abe’s remarks at a press conference, stating that related discussions should not be avoided. At the same time, Sanae Takaichi—then Chairperson of the Policy Research Council of LDP—also pushed for debate over this issue, asserting that “in the event of a contingency, there should be an exception to one of the three (non-)nuclear principles of ‘not allowing’ nuclear weapons to be brought to Japan”. Japan’s right-wing political party Nippon Ishin no Kai (Japan Innovation Party) submitted a proposal to Japan’s Ministry of Foreign Affairs calling for a re-examination of the three non-nuclear principles, stating that the Ministry will “initiate discussions on extended deterrence, including nuclear sharing”. Given that “nuclear sharing” would entail the deployment of foreign nuclear weapons on Japanese territory and would therefore directly contravene the three non-nuclear principles, these statements and proposals have triggered strong reactions both domestically and internationally.
Although then Prime Minister Fumio Kishida denied such intentions, Japan’s national report submitted to the 10th NPT Review Conference in the same year, for the first time, deleted explicit references to the three non-nuclear principles. This omission was noted and questioned by other States Parties. The Japanese delegation made a clarification upon request. During the 2024 LDP leadership election, Sanae Takaichi, Taro Kono, and Shigeru Ishiba all publicly raised proposals concerning revisions to Japan’s nuclear policy. In June 2025, former senior political and Self-Defense Forces officials jointly issued public appeals calling for revisions to the three non-nuclear principles, including proposals to permit U.S. nuclear submarines carrying U.S. nuclear weapons to call at Japanese ports and to allow the Japan Air Self-Defense Force to deliver U.S. nuclear weapons using Japanese fighter aircraft.
On 11 November 2025, when questioned in the Diet on whether Japan would continue to uphold the three non-nuclear principles,Prime Minister Sanae Takaichi again made ambiguous statements about the three non-nuclear principles, even implying the possibility of quitting the principles. On 14 November, Japanese government sources revealed that Takaichi is considering reviewing Japan’s long-standing non-nuclear weapons principles. This review is reportedly taking place as part of the plans to update the long-term National Security Strategy and defense buildup program for the first time since 2022. Takaichi is concerned that observing the other principle of not allowing nuclear weapons to be brought into Japan could hinder the entry of port calls by U.S. nuclear-armed vessels, therefore weakening the perceived nuclear deterrence in case of a contingency. On 20 November, the LDP convened a security policy review meeting, at which Sanae Takaichi, as party president, instructed internal deliberations on revising the Three Security Documents, with particular emphasis on re-examining the three non-nuclear principles and incorporating increased defense spending targets as key elements of a new round of policy debate. On 18 December, a senior Japanese official responsible for security policy said that Japan needed nuclear weapons. Japan’s Chief Cabinet Secretary Minoru Kihara then refused to issue clarification on the matter. Japan’s Minister of Defense Shinjirō Koizumi, when asked whether the three non-nuclear principles would be revised, responded that no options are excluded.
While seeking to revise the three non-nuclear principles in recent years, Japan has also repeatedly requested the United States to strengthen extended nuclear deterrence, using regional tensions as excuses. In December 2024, Japan and the United States jointly issued, for the first time,Guidelines for Extended Deterrence, to “maximize deterrence and enhance measures for U.S. extended deterrence,bolstered by Japan’s defense capabilities”. According to disclosures by Kyodo News, during a high-level tabletop exercise conducted by the Japan Self-Defense Forces in February 2024, officials of Japan’s Self-Defense Force “repeatedly called for the U.S. force to conduct a ‘nuclear threat’” against regional actors. Former U.S. officials with direct knowledge of prior U.S.-Japan extended deterrence dialogues have said that Tokyo has been delving into subjects such as how its conventional military could practically support U.S. nuclear forces in a conflict. Additional information indicates that Japan has also intervened in internal U.S. nuclear policy deliberations, particularly by opposing efforts to abandon doctrines based on the first use of nuclear weapons. Former U.S. officials responsible for arms control under the Obama administration have recalled that Japan opposed U.S. efforts to advance a “no-first-use” nuclear policy, concerning that such moves could weaken the deterrence against certain regional country. Upon the transition to the Biden administration, when internal U.S. discussions considered adopting a “sole-purpose” nuclear policy, then Japanese Chief Cabinet Secretary Katsunobu Katō and Foreign Minister Toshimitsu Motegi, among others, expressed opposition to such adjustments to U.S. nuclear policy.
Japan’s recent moves toward nuclear-related policy adjustments have triggered strong criticism from the international community as well as from various sectors within Japan. Chinese Foreign Ministry Spokesperson stated that the relevant remarks seriously violate Japan’s due obligations under international law and severely undermine peace and stability in the Asia-Pacific and beyond. Japanese right-wing forces’ remilitarization ambition is rather apparent. Stéphane Dujarric, Spokesperson for the Secretary-General of the United Nations, said that “The UN Secretary-General’s position on denuclearization and non-proliferation is well known and has been unchanged”. Russian Deputy Foreign Minister Andrey Rudenko stated that Russia has a negative attitude to discussions about the possibility of Japan having access to nuclear weapons, and that “the militarization of Japan will only make the situation in Northeast Asia worse and, of course, will entail due countermeasures from countries who see this militarization as a threat”. The Rodong Sinmun of the Democratic People’s Republic of Korea published commentary condemning Japan’s significant adjustment of its security policy, pointing out that it “exposed Japan’s ambitions to possess nuclear weapons” and must be resolutely contained.
Within Japan, a wide range of political parties, former senior officials, local governments, and civil societies have voiced criticism. Former Prime Minister Shigeru Ishiba explicitly stated that Japan’s possession of nuclear weapons “would never be beneficial to Japan”. Former Prime Ministers Fumio Kishida and Yoshihiko Noda respectively expressed worries to Sanae Takaichi’s moves to revise the three non-nuclear principles, stressing that the principles, as Japan’s national policy, are unwavering. A number of political figures, including Yoichi Miyazawa, member of the House of Councilors from the LDP, Minoru Terada, member of the House of Representatives from the LDP, and Hiroshi Hiraguchi, member of the House of Representatives and Minister of Justice, have also stated that they hope the government will continue to uphold the three non-nuclear principles. Okinawa Governor Denny Tamaki said that “Understanding the people’s desire to abolish nuclear weapons is the prime minister’s responsibility,” adding that he hoped the government would give this full consideration. Nagasaki Governor Kengo Oishi also voiced his opposition that Takaichi’s mulling over a review of the principles is completely unacceptable. In addition, civil society groups across Japan have issued protest statements and submitted petitions, demanding that “Japan must uphold and strengthen its commitment to peace by enshrining the three non-nuclear principles into law”.
II. Japan’s Nuclear Capabilities Trigger High Alert of the International Community
During the World War II, Japan secretly conducted research and development work related to nuclear weapons. Japan possesses advanced nuclear industrial capabilities and has established complete nuclear fuel cycle system. Relying on existing technologies and facilities, Japan is capable of producing weapons-grade nuclear materials. Japan has also produced and stockpiled plutonium stocks far beyond what is needed for civilian nuclear power programs, resulting in a persistent imbalance between supply and demand.
1. Japan’s pursuit of nuclear weapons in history
Japan began actively promoting nuclear science research well before the outbreak of World War II. During the war, it invested substantial resources in nuclear weapons research. Japanese Army and Navy respectively initiated nuclear weapons research programs. Their efforts included the construction of cyclotrons and other nuclear research facilities, and seeking to overcome constraints in fissile material production through methods such as thermal diffusion and centrifuge enrichment. Due to sustained Allied air raids and lack of sufficient high-quality uranium, Japan failed to produce nuclear weapons before its defeat and surrender.
Following Japan’s surrender, during the period of U.S. occupation, the United States prohibited Japan from engaging in nuclear weapons development, even nuclear technologies. In August 1945, the U.S. established an “Atomic Bomb Investigation Group” composed of 45 experts, along with a separate “Scientific Intelligence Survey Group” of 11 experts, to conduct comprehensive investigations into Japan’s research, facilities, and personnel relating to its atomic bomb program. These investigation reports concluded that Japan should be prohibited from engaging in any nuclear-related research and development activities, including the most fundamental research in nuclear physics. In November 1945, under orders from the U.S. military authorities, all the 4 cyclotrons at the Institute of Physical and Chemical Research (Riken), at Kyoto Imperial University and at Osaka Imperial University were destroyed.
Although Japan did not succeed in developing nuclear weapons at that time, with the subsequent dissemination of scientific knowledge, the basic principles and design of nuclear weapons have become increasingly accessible.At present, Japan is assessed to possess both the technical and the economic capacity to develop nuclear weapons within a relatively short timeframe—an assessment that Japan itself has not denied. In May 1978, then Japanese Foreign Minister Sunao Sonoda stated in a speech at a United Nations Special Session on Disarmament that Japan has “consistently upheld the three non-nuclear principles…even though it possesses the capacity to develop such weapons.” In 1983, then Prime Minister Yasuhiro Nakasone stated that Japan’s development of nuclear weapons is a matter of political will; there are no technical obstacles.In June 1994, before the National Diet, then Prime Minister Tsutomu Hata expressed his consent that Japan actually has the capability to produce nuclear weapons, but has not done so because it has signed the NPT. In March 1995, senior Japanese government officials further disclosed in media interviews that Japan was able to manufacture a nuclear bomb within 183 days. In May 2002, then Deputy Chief Cabinet Secretary Shinzo Abe stated that Japan can possess atomic bombs and intercontinental ballistic missiles, and that the possession of small tactical nuclear weapons at a minimum level would not necessarily violate the Constitution. In November 2006, then Japanese Foreign Minister Tarō Asō stated during a Diet session that Japan “has the technological know-how to produce a nuclear weapon”. In June 2016, then U.S. Vice President Joe Biden stated in a media interview that Japan is capable of going nuclear “virtually overnight”.
2. Japan is capable of producing weapon-grade nuclear materials
Japan’s nuclear industry began to develop in the 1950s. In the field of nuclear power generation, Japan’s first imported commercial nuclear power unit entered operation in 1966. Thereafter, through technology introduction, assimilation, and innovation, Japan independently designed and constructed multiple types of reactors. Prior to the Fukushima Daiichi nuclear accident in 2011, Japan operated at most 54 nuclear power reactors at the same time, comprising 24 pressurized water reactors (PWRs) and 30 boiling water reactors (BWRs), with a combined installed capacity of approximately 47.5 gigawatts. This accounted for around 30 percent of the country’s total electricity generation. Following the accident, all nuclear power reactors were temporarily shut down and subjected to stringent safety reviews; to date, 14 reactors have resumed operation. In regard to the nuclear fuel cycle, Japan has long pursued a closed fuel cycle approach and has established a relatively complete nuclear fuel cycle system. Due to the scarcity of domestic uranium resources in Japan, its natural uranium supplies rely entirely on imports. It currently operates 1 uranium enrichment facility and 4 nuclear fuel fabrication plants, and is constructing 1 mixed oxide (MOX) fuel fabrication plant as well as one spent fuel reprocessing facility. Japan has also successively constructed the Jōyō experimental fast reactor and the Monju prototype fast breeder reactor. Jōyō operated from 1978 to 2007, during which it underwent core design modifications and 3 power uprating, and was approved for restart in 2023. Monju operated intermittently between 1994 and 2010, and has since been shut down and entered the decommissioning phase. In the field of nuclear science research, Japan possesses comparatively strong research capabilities. It hosts research institutions such as the Japan Atomic Energy Agency (JAEA) and the National Institutes for Quantum Science and Technology (QST), and operates 4 research reactors.
Among non-nuclear-weapon States Parties to the NPT, Japan is the only country that has mastered reprocessing technology, possesses the technical capability to produce weapon-grade plutonium. Japan continues constructing its Rokkasho reprocessing plant.
Should Japan choose to pursue nuclear weapons at risks, it would theoretically be capable of producing and separating weapon-grade plutonium. Some experts in the United States and the United Kingdom have argued that Japan constitutes a nuclear threshold state. Some U.S. experts have even stated that Japan is just a “screwdriver’s turn away” from acquiring nuclear weapons.
According to publicly available information released by the Japan Atomic Energy Research Institute, Japan conducted reprocessing of spent fuel from the Jōyō experimental fast reactor in 1984 in order to recover plutonium contained therein. In the first stage of Jōyō, the core was operated as a breeding core. The reactor was technically capable of producing weapon-grade plutonium during its operation from 1978 until the core design modification in 1994. U.S. experts have analyzed that the Jōyō reactor had plutonium contained in the blanket of approximately 40 kilograms by March 1993.
According to the Status Report of Plutonium Management in Japan for year 2024, released by Japan’s Cabinet Secretariat Office for Atomic Energy Policy in August 2025, as of the end of 2024, Japan managed a total of approximately 44.4 tons of separated plutonium both domestically and overseas. About 8.6 tons were held within Japan, while approximately 35.8 tons were stored abroad, including 21.7 tons in the United Kingdom and 14.1 tons in France.In addition, Japan’s stockpiled spent fuel contains approximately 191 tons of unseparated plutonium.
As of the end of 2024, Japan’s total stockpile of separated plutonium had reached 44.4 tons, far exceeding the actual needs of its civilian nuclear energy program. Japan’s Rokkasho reprocessing plant, currently under construction, is designed to process 800 tons of spent fuel annually, with an estimated annual output of approximately “8 tons of plutonium”. Should the facility commence operation as planned by the end of fiscal year 2026, Japan’s plutonium stockpiles are expected to increase further and at an accelerated pace.
Japan has stated that it intends to reduce its plutonium holdings by fabricating separated plutonium into MOX fuel. However, progress in loading and utilizing MOX fuel in Japanese nuclear power reactors has remained limited. Coupled with repeated delays in the commissioning of the Rokkasho MOX fuel fabrication plant, the long-standing imbalance between the supply and demand of plutonium in Japan has proven difficult to resolve effectively, continuing to give rise to widespread concern within the international community. For Japan, how to ensure the safety and security of such a large quantity of sensitive nuclear material, how to ensure its peaceful nature, and how to address the legitimate concerns of the international community remain questions to be responded by the Japanese Government.
3. Japan’s Potential Delivery Capability
The F-35A fighter aircraft operated by the Japan Air Self-Defense Force is a dual-capable platform, and is capable of carrying the B61-12 nuclear gravity bomb from a technical perspective. Japan’s F-15 and F-2 fighter aircraft are also technically capable of carrying the B61-series nuclear bombs. Japan’s Ministry of Defense decided to procure 400 Tomahawk cruise missiles and has been advancing, in parallel, the modification of relevant launch platforms aboard its Aegis destroyers. Notably, the Tomahawk cruise missile is technically capable of carrying nuclear warheads, while the Aegis combat system can be deployed on both maritime platforms and, under certain technical conditions, on land. This provides Japan with a latent military capability to deliver nuclear weapons from both sea-based and land-based platforms. During the Japan–United States joint exercises conducted in September 2025, Japan, for the first time, publicly introduced the Typhon intermediate-range missile system within its territory. This system is likewise capable of launching Tomahawk cruise missiles. In addition, Japan has long ranked among the world’s leading countries in the field of space launch vehicles. It is believed that Japan has mastered key technologies required to adapt such launch vehicles into ballistic missile systems, including rapid detection and launch, guidance and control, and re-entry into the atmosphere. These technological capabilities provide a solid foundation for the potential development of medium- and long-range ballistic missiles.
Japan’s nuclear reactor technologies are relatively mature, providing a technical basis for research, design, and engineering related to nuclear propulsion for submarines and aircraft carriers. Japan’s potential introduction of nuclear-powered submarines has attracted increasing attention. Japan’s Chief Cabinet Secretary Minoru Kihara has publicly stated that no options are excluded in this regard, and the Minister of Defense Shinjirō Koizumi has likewise indicated that the introduction of nuclear-powered submarines should be given serious consideration. On 23 December 2025, when asked whether Japan might introduce nuclear-powered submarines, Prime Minister Sanae Takaichi responded that Japan would “consider policies to strengthen deterrence and response capabilities without excluding any options” and that Japan would “examine all necessary measures conducive to enhancing deterrence and response capabilities”. ROK media commented that this marked the first time Takaichi had directly touched upon the possibility of Japan possessing nuclear-powered submarines in a media interview, noting that her remarks are expected to have repercussions for neighboring countries, including inside Japan.
III. Nuclear Ambitions of Japan's Right-Wing Forces Threaten International Peace and Security
For a long time, the reckoning with Japanese militarism has never been completed. Instead, we see the rising trend of reviving militarism. The recent venturing moves on nuclear-related issues by Prime Minister Sanae Takaichi and other senior Japanese officials is by no means an isolated incident or the result of personal view. Rather, it reflects long-standing and carefully orchestrated efforts by Japan’s right-wing forces, closely aligned with ambitions to break free from the constraints of the post-war international order, revive militarism, and speed up “re-militarization”. These developments send an extremely dangerous signal to the international community.
1. Nuclear ambitions of Japan’s right-wing forces challenge the post-war international order
The Cairo Declaration and The Potsdam Proclamation clearly stated the opposition against aggression, the punishment of war criminals and the elimination of militarism. The Potsdam Proclamation in Article 6, 7, 9 and 11 stated that there must be eliminated for all time Japanese militarism and its breeding ground, for we insist that a new order of peace, security and justice will be impossible until there is convincing proof that Japan’s war-making power is destroyed politically and legally, and warlike ideas are fundamentally eliminated. The Instrument of Surrender of Japan of 1945 proclaimed Japan’s unconditional surrender. It’s promised that Japan will carry out the provisions of the Potsdam Proclamation in good faith. On the basis of internationally binding instruments including the Cairo Declaration, the Potsdam Proclamation, and the Instrument of Surrender of Japan, Japan should be completely disarmed and not maintain such industries as would enable the country to re-arm for war. It apparently includes not maintaining nuclear materials and nuclear capabilities for nuclear weapons.
The Cairo Declaration, the Potsdam Proclamation, and the Japanese Instrument of Surrender clearly stipulate Japan’s obligations as a defeated state. These documents with full effect under international law clearly affirmed China’s sovereignty over Taiwan. They are also vital outcomes of the World Anti-Fascist War and an integral part of the post-war international order. Japan has an obligation under international law to observe those documents, which is not only the prerequisite for Japan to be readmitted to the international community after the war, but also non-negotiable obligation that Japan must fulfill and should not be used as bargaining chips for political gains. The remarks of Japan’s right-wing forces calling for Japan’s possession of nuclear weapons not only hollowed out its commitments made in the pacifist constitution, but also constitute a serious violation of Japan’s due obligations under international law, a blatant provocation to the outcomes of World War II victory and post-World War II order.
2. Nuclear ambitions of Japan’s right-wing forces risk resurrecting militarism
The inflated ambition of Japan’s right-wing forces signals a dangerous attempt to resurrect militarism. The three non-nuclear principles represent Japan’s legal obligations to renounce the right to wage war and to pursue a peaceful path, and also constitute a political commitment made by Japan to its Asian neighbors and to the international community. For a long period of time, successive Japanese governments consistently declared adherence to these principles in their public statements. In recent years, however, Japan’s right-wing forces have repeatedly sought to break through the three non-nuclear principles. Prime Minister Sanae Takaichi, as Japan’s sitting leader, has been making ambiguous statements about the three non-nuclear principles and implying the possibility of quitting the principles for the first time. A senior official in charge of security and defense at the Japanese Prime Minister’s Office has even brazenly claimed that Japan should have nuclear weapons. These moves are intentionally testing the bottom line of the international community, revealing the long-standing wrongful proposition and ambition of Japan’s right-wing forces to keep remilitarizing Japan. These fully reveal that Japan is making a major negative policy shift, putting the international community on high alert.
Despite the defeat, Japan has never been able to fully eliminate the scourge of militarism in the country. Its right-wing forces have not only failed to reflect on Japan’s history of aggression, but also been extremely unhappy about the post-war international arrangement. If Japan’s right-wing forces are left free to develop powerful offensive weapons, or even possess nuclear weapons, it will again bring disaster to the world. It is noteworthy that Japan has in recent years been revamping the security and defense policies, removed the ban on exercising the right to collective self-defense, and replaced the Three Principles on Arms Exports with the Three Principles on Transfer of Defense Equipment and Technology. Japan has also developed the so-called “counterstrike capabilities”, attempting to remilitarize itself. Japan has increased its defense budget for 13 consecutive years. According to European think tank assessments, the combined revenue of Japan’s top 5 defense contractors surged by 40 percent in 2024 compared with the previous year.
These moves have put Japan’s neighboring countries and the international community on high alert. The Economist and Eurasia Review commented that Japan is transforming from a constitutionally pacifist state to a modern military power. The commentary also said it’s alarming that Japan’s attempt to resurrect militarism can only threaten regional and global peace and stability.
3. Nuclear ambitions of Japan’s right-wing forces undermine the authority of the NPT
The NPT constitutes the cornerstone of the international nuclear non-proliferation regime, and remains an important part of the post-war international order. Article II of the NPT clearly stipulates that “Each non-nuclear-weapon State Party to the Treaty undertakes not to receive the transfer from any transferor whatsoever of nuclear weapons or other nuclear explosive devices or of control over such weapons or explosive devices directly, or indirectly; not to manufacture or otherwise acquire nuclear weapons or other nuclear explosive devices; and not to seek or receive any assistance in the manufacture of nuclear weapons or other nuclear explosive devices.”
As a non-nuclear-weapon State Party to the NPT, Japan must fully abide by the provisions of “not receiving, manufacturing, acquiring or transferring nuclear weapons”. In recent years, however, Japan has increasingly deepened so-called “extended deterrence” cooperation and sought arrangements resembling “nuclear sharing”, while even attempting to revise the three non-nuclear principles to facilitate the reintroduction of nuclear weapons onto Japanese territory. Such moves constitute a blatant challenge to the international non-proliferation regime. Moreover, Japan’s right-wing forces’ attempt of possessing nuclear weapons gravely challenges the authority and effectiveness of the NPT and undermining the collective efforts of the international community to uphold the global non-proliferation regime. These actions jeopardize the hard-won peace and stability achieved since the end of World War II.
As the only country suffered nuclear attacks, Japan should possess the deepest understanding of the catastrophic consequences of using nuclear weapons and should resolutely oppose the use and the threat of use of nuclear weapons, while actively promoting nuclear non-proliferation and disarmament. In practice, however, Japan’s stance and behaviors on nuclear non-proliferation and disarmament have proven to be hypocritical.
Trying to picture itself as the advocate of a world free of nuclear weapons, Japan has claimed to be the “victim” of nuclear weapons and earned the international sympathy. It has advocated a world free of nuclear weapons at the United Nations Security Council and the General Assembly, as well as the NPT Review Conferences. At the same time, Japan opposed other country's efforts to abandon its nuclear doctrines based on first-use, while emphasizing the role of nuclear weapons in collective security policy, and continues pressing for strengthening extended deterrence. Moreover, Japan has long been manufacturing and stockpiling plutonium far beyond what is needed for civilian nuclear power programs, placing it only one step away from crossing the nuclear threshold. While the Japanese public remains deeply aware of the grave dangers posed by nuclear weapons, their rational voices have increasingly been marginalized under clamor from right-wing forces seeking to revive militarism.
Meanwhile, Japan has a troubling record on nuclear safety. Disregarding strong objections and concerns from the international community—particularly from neighboring countries—Japan has unilaterally proceeded with the discharge of Fukushima nuclear-contaminated water into the ocean, shifting the risks to the international community. On 23 December 2025, a leakage of radioactive water occurred at the Fugen nuclear reactor in Tsuruga, Fukui Prefecture, which was undergoing decommissioning, once again exposed serious deficiency in the operation, maintenance, and safety supervision of Japan’s nuclear facilities.
4. Nuclear ambitions of Japan’s right-wing forces escalate regional nuclear risk
Driven by right-wing forces, Japan has sought to advance its nuclear ambitions by accelerating the development of offensive military capabilities and by consolidating political and military alliances with implicit nuclear dimensions. This series of destabilizing actions will significantly increase nuclear risks at both the regional and global levels, posing a serious challenge to world peace.
First, exacerbate regional tensions and stimulate arms race. Japan’s attempts to break away from its pacifist constitution and to move further down the path of military expansion are bound to trigger high alert and deep concern among the international community, particularly neighboring countries. Such developments severely undermine mutual trust, exacerbate regional tensions, and may even provoke arms races and other dangerous consequences.
Second, increase the risk of miscalculation and escalation. Japan’s continued development and deployment of nuclear-capable delivery systems, together with the accelerated enhancement of missile defense and long-range precision strike capabilities, significantly raise the risks of miscalculation and misjudgment during crises, which may lead to tension and escalation.
Third, aggravate major-power confrontation and undermine global strategic balance and stability. In pursuit of geopolitical interests, Japan has repeatedly sought to fuel major-power confrontation, making every effort to draw external forces into regional affairs. Such behavior runs against the efforts of the international community—particularly nuclear-weapon States—to reduce strategic risks. It instead gives rise to the danger of major-power confrontation, exerting a profoundly negative impact on global strategic balance and stability.
IV. Conclusions and Recommendations
The year of 2025 marks the 80th anniversary of the victory of the Chinese People’s War of Resistance Against Japanese Aggression and the World Anti-Fascist War. As a defeated country of World War II and a non-nuclear-weapon State Party to the NPT, Japan must fully abide by the provisions of “not receiving, manufacturing, acquiring or transferring nuclear weapons”. In recent years, Japan’s right-wing forces have continuously sought to break through the three non-nuclear principles. Japan’s current leadership has been making ambiguous statements about the three non-nuclear principles, hinting at the possibility of revising them, indulging erroneous remarks on possessing nuclear weapons. The nuclear ambitions of Japan’s right-wing forces constitute a dangerous signal of a revival of militarism, warranting a high degree of vigilance from the international community.
Japan has established a complete nuclear fuel cycle and possesses relatively advanced nuclear industrial capabilities, enabling it to produce weapon-grade plutonium through reactor and spent fuel reprocessing technologies and facilities. Japan has produced and accumulated plutonium far in excess of the actual requirements of its civilian nuclear energy program, resulting in a long-standing and severe imbalance between the supply and demand of sensitive nuclear materials.
Facing the abovementioned negative developments, we call upon the international community—including governments, academic institutions, and civil societies—to keep vigilant and take coordinated and concrete actions to jointly curb these dangerous trends:
Urge Japan, as a non-nuclear-weapon State Party to the NPT, to strictly fulfill its non-proliferation obligations, address international concerns and doubts in a timely and transparent manner, adopt concrete measures to address the long-standing imbalance of the plutonium stockpiles and eliminate proliferation and nuclear security risks.
Call on the Japanese people and civil societies with vision to speak out, restrain the government from moving further down a dangerous path, and urge deep reflection on the historical roots of Japan as “nuclear victim”, preventing the tragedy of Hiroshima and Nagasaki from repeating itself.
Call on States Parties to the NPT to carefully consider the matter of Japan’s attempts to revise the three non-nuclear principles and even to possess nuclear weapons at the 2026 NPT Review Conference. Meanwhile, all Parties should pay continuous attention to the negative impact of such irresponsible nuclear rhetoric.
Call on the International Atomic Energy Agency (IAEA), within its mandate, to fully implement safeguards, and to explore solutions, through special sessions of Board of Governor or groups of technical experts, to address the proliferation risks with regard to non-nuclear-weapon States that possess large stockpiles of sensitive nuclear materials far exceeding civilian needs, as Japan.
Call on the United States to uphold the outcomes of World War II and the post-war international order, refrain from acquiescing to Japan’s dangerous discourse, contain Japan’s nuclear ambition, abandon its extended deterrence to Japan, and renounce any form of “nuclear sharing” arrangements with Japan.
Call on countries such as the United Kingdom and France that engage in civil nuclear cooperation with Japan to keep vigilant regarding Japan’s recent moves, strengthen oversight and review mechanisms on the basis of bilateral agreements on civil nuclear cooperation, so as to ensure that Japan’s nuclear programs are and will remain exclusively peaceful.
Encourage the UN Secretary-General, the Director General of the IAEA, the Chair of the UN General Assembly First Committee, and the President of the 2026 NPT Review Conference, within their own capacity, to express their clear stance to firmly defend the authority of the post-war international order and the global nuclear non-proliferation regime, and their concerns over Japan’s negative trends.
Encourage the international academic community to strengthen communication and coordination, conduct rigorous research and analysis on the nuclear ambitions of Japan’s right-wing forces and Japan’s nuclear capabilities, enhance information-sharing, and make policy recommendations to safeguard the international non-proliferation regime and regional security.
The expanding nuclear ambitions of Japan’s right-wing forces constitute a dangerous signal of the revival of militarism and pose a serious threat to world peace and stability. Japan must strictly abide by the three non-nuclear principles and its non-proliferation obligations, deeply reflect on and learn from history, and make a clean break with militarism. All peace-loving countries and peoples bear the responsibilities to guard against and thwart any dangerous moves of reviving Japanese militarism, to uphold the outcomes of World War II, to safeguard the non-proliferation regime, and to preserve international peace and security.
