Nuclear Shadows In Japan–China Relations – OpEd

Grievances, border disputes, and political rivalries have long been major factors in Japan-China relations. In recent times, the nuclear factor has increasingly become another factor that can lead to tensions. Latent Japanese nuclear capabilities, Chinese concerns over Japan’s nuclear technology programmes and the changes in the US extended deterrence system have all contributed to increased tensions in the East Asian region over nuclear issues. If left unchecked, the nuclear factor could destabilise the region. These tensions could be addressed through diplomacy, increased transparency and a stronger security framework in the region. This paper will discuss the background of the nuclear tensions in Japan-China relations, their impact on the stability of the region, and finally, the possible way out of the difficulties that may arise in the region.

To understand the nuclear dimension in Japan–China relations, one has to look into the past of this bilateral relationship. Japan’s post-war constitution and its “three non-nuclear principles” aimed at preventing Japan from becoming a military power like in the Second World War era, and also at enabling the country to atone for its aggression during wartime and the atomic bombings of Hiroshima and Nagasaki. This resulted in Japan having what could be called an “implicit capacity” to become a nuclear weapons state, thanks to the civilian use of nuclear energy and the storage of plutonium. As for China, it declared itself a nuclear power in 1964. In terms of security, looking at the capacity of Japan to become a nuclear weapons state is a strategic issue for Beijing, which bears in mind the numerous and painful aggressions it has suffered in the course of its history with Japan.

The nuclear debate in Japan has been intensifying in recent years in the backdrop of heightened security tensions in the Asia-Pacific region. North Korea’s continuing missile tests and its development of nuclear weapons have escalated Japanese security concerns. China’s rapid build-up of its military capability and its aggressive posturing in the East and South China Seas have further increased the pressure on Japan. There are differing opinions within Japan’s ruling Liberal Democratic Party (LDP) on whether to revise the country’s three non-nuclear principles in response to Japan’s changing security circumstances. But the Japanese public remains firmly opposed to nuclear arms. While China’s concerns about the debate on revising Japan’s principles have been noted, Beijing views it as an expression of Japan’s return to militarism, which serves to boost China’s domestic nationalistic sentiment and serves as a warning to other countries in the region of Japan’s growing military capability.

China has its own reasons to regard Japan as a nuclear threat. From a strategic perspective, if Japan developed nuclear weapons, it would negatively impact China’s own strategic position in the region and undermine the realisation of China’s deterrence strategy. Politically, Japan, as a destabilising factor in the region, also conforms to China’s strategy of resisting the US containment and realising regional stability. China has also criticised Japan for having a large amount of plutonium and demanded that Japan give “assurances” to the International Atomic Energy Agency (IAEA) not to use it for nuclear weapons. Japan’s recent decision to release the Fukushima wastewater into the ocean also heightened the distrust of China towards Japan. The Chinese view that Japan has been handling the Fukushima nuclear disaster in a highly irresponsible manner and that the decision to dump wastewater into the ocean has further strengthened their doubts.

The underlying reasons for the current tension between Japan and South Korea are being exacerbated by the security situation in the region. While Japan is covered by the U.S. nuclear umbrella as part of the extended deterrence, there are growing concerns that the U.S. capacity and willingness to carry out this commitment in the future are in decline. Tokyo is therefore starting to contemplate developing its own independent deterrence capabilities. Meanwhile, there are reports that Seoul is also considering acquiring nuclear deterrence capabilities. The fact that China is also in the process of enhancing its own nuclear forces to counter the U.S. does not make the situation easier. Any further flare-up of the current tensions over Taiwan or the Senkaku/Diaoyu islands could then escalate into a full-blown crisis due to miscalculations.

The future of the world looks very unstable, and this makes the Asian security situation unstable. Japan’s latent nuclear capability, China’s sensitivities and lack of US security guarantees all increase instability in what used to be a stable security triangle. It is uncertain what can be done to smooth the path for Japan’s quest for defence capability in a situation in which there are a number of hurdles to be cleared. These hurdles include the domestic Japanese political conflict with the changing position of Asia towards a rising Japan; the need to reassure China in a manner which is not in contradiction with Japan’s own defence requirements; and the serious threat to regional stability that is posed by the untamed and uncontrolled behaviour of North Korea. Nuclear politics in Asia may develop in the manner of a vicious spiral of increasing distrust, which would make it difficult for other states to prevent them from seeking to develop nuclear weapons.

Any attempt to resolve the present strains in the Sino-Japanese relationship will have to be on the basis of full disclosure, dialogue and reform of the security apparatus. Japan must reaffirm its commitment to the three principles of non-proliferation, and at the same time give a more candid explanation of its plutonium stockpiles, to alleviate Chinese and international concern. China has to enter into a dialogue with Japan, which recognises the gravity of Japanese security concerns and is not driven into a reflexive rejection of them as based on nothing other than militarism. The US has to confirm its obligations of extended deterrence towards Japan and South Korea, to dissuade them from the inclination to acquire their own nuclear capacities. The Sino-Japanese region will have to build trust by instituting confidence-building measures and communication networks to help pre-empt possible misunderstandings. A useful multilateral framework could be provided by the UN and the IAEA to enhance the possibility of international monitoring and assurance. In any case, the purpose of the security dialogue should be to preclude the need to contemplate nuclear options.

The recent nuclear dispute between Japan and China is only a small part of the overall security uncertainties existing in the East Asia region. Japan’s post-war development as a peace-loving nation in line with the principles of the UN Charter is in stark contrast to the country’s current level of nuclear technology and the increasing concerns among the Japanese population about national security. China’s concerns, which are rooted in historical and security-related factors, have been exacerbated in recent years by Japan’s rightward shift and its confirmation of its nuclear research activities, in light of Japan’s increasing dependence on foreign oil. In any case, it will be very difficult to solve the non-proliferation problems, reduce the current tensions and prevent an escalation of the conflict in the highly unstable regional environment that currently exists. However, there are also other options, such as greater openness, diplomacy and alliances, and Japan, China and the US can act prudently in order to avoid creating an environment conducive to an arms race in the region. The nuclear issue is not merely an arms race, but also a factor of major importance for the stability of the region of East Asia, which is becoming increasingly significant politically, economically and militarily.

The opinions expressed in this article are his own.

Davenport, K. (2026, February 5). In 2026, a growing risk of nuclear proliferation. Just Security. https://www.justsecurity.org/129480/risk-nuclear-proliferation-2026/ 

Lin, B., & Govella, K. (2025/2026). Escalating Japan–China tensions: Insights from the past and prospects for the future. Centre for Strategic and International Studies (CSIS). https://www.csis.org/analysis/escalating-japan-china-tensions-insights-past-and-prospects-future


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