Assessing Japan’s 2026 Defence White Paper

Summary

The emphasis on ‘new ways of warfare’ in the Defense of Japan 2026, released on 4 August, indicates Japan’s desire to play a more assertive role. However, the emphasis on US primacy raises questions of policy independence. The document also unveils tensions between automation and staffing, as well as between excessive self-reliance and positive international cooperation in defence technology. As Prime Minister Sanae Takaichi attempts to bring Japan closer to the US while bolstering native defence capabilities, the 2026 edition conveys both the prospects and challenges inherent in her quest.

Introduction

Japan’s Minister of Defence Shinjiro Koizumi released the 2026 edition of his ministry’s flagship white paper, ‘Defense of Japan 2026’, on 4 August.^[1] The 598-page 2026 edition, currently available in unabridged form only in Japanese,^[2] provides an opportunity to measure incremental changes in Japanese strategic policy and its responses to changes in the strategic environment.

The current edition is especially significant as the first to be released under Prime Minister Sanae Takaichi, whose longstanding advocacy of a more active Japanese role in regional security is well known. Her assumption of office in 2025 preceded the rapid and substantial deterioration in relations with China (largely due to her off-the-cuff remarks on Taiwan during a Diet session in November 2025), growing tensions with Russia and continued anxiety over the Democratic People’s Republic of Korea (DPRK).

Meanwhile, US President Donald Trump, by overturning decades-long patterns of Japanese over-reliance on US security guarantees, strengthened Takaichi’s efforts to break free of Japan’s post-war pacifism and attain a measure of self-reliance. The current edition of the white paper deserves attention as a milestone laying out the contours of Japan’s emerging response to the changing security situation.

Japan’s Threat Perception

As Part 1 of the white paper makes clear, Japan sees itself in a hostile neighbourhood. ‘The Greatest Trial of the Postwar Era’ is, according to it, a product of unilateral attempts to change the status quo by ‘[s]tates that do not share universal values or political and economic systems based on such values’, balance-of-power contestation between the leading states, ‘[r]apid developments in science and technology’ and the emergence of activities below the threshold of belligerence.^[3] The return of interstate war also exercises the drafters of the white paper to some extent, with Russia’s 2022 invasion of Ukraine attracting particular attention.^[4]

Regionally, the white paper clearly identifies China as the ‘unprecedented and the greatest strategic challenge’ for Japan. Among the reasons listed, one immediately notes the not-insignificant space accorded to concerns about Taiwan.^[5] While the level of detail is understandable given the Taiwan Strait’s importance to Japanese strategists, the language appears to serve three additional purposes.

Firstly, it seems to be driving and legitimising the ‘Taiwan panic’ currently prevalent in Japanese policymaking circles, whereby a sense of proprietorial concern for the self-ruled island’s welfare in its own right is implied. Secondly, and not unrelatedly, the white paper’s discursive emphasis seems to be doing the domestic political work of substantiating Prime Minister Takaichi’s comments on Taiwan in November 2025, translating them into policy. Thirdly, the language on Taiwan seems designed to convey opposition to China’s goals, especially in the section that comments on Beijing’s stance.

The DPRK ‘pose[s] an even more grave and imminent threat to Japan’s national security than ever before’ through its ‘military activities’, a significant elevation of Japan’s threat perception level.^[6] Aside from the nuclear and missile development threat, Pyongyang’s active collaboration with Russia also appears as a threat factor. Meanwhile, Russia itself is ‘a strong security concern’ for Japan, largely as it undergoes greater military mobilisation and increasingly collaborates with China to ‘continu[e] active military activities in the vicinity of Japan’ and ‘the Northern Territories’ (the Japan-claimed, Russia-administered islands also known as the Southern Kuriles).^[7] Notably, the ‘Middle East’ is also mentioned as a key security challenge, with the Strait of Hormuz amplifying Japan’s economic insecurity.^[8]

Japan’s Core Strategic Direction

Part 2 of the document, in association with Chapter 4 of the previous part, elaborates on Japan’s response to the security environment mentioned above. The key thesis of this part is:

憲法のもと、専守防衛に徹し、他国に脅威を与えるような軍事大国とな

らないとの基本方針に従い、文民統制を確保し、非核三原則を政策上の

方針として堅持している。^[9]

Under the Constitution, Japan, in line with the basic policies of maintaining the Exclusively Defense-Oriented Policy and not becoming a military power that poses a threat to other countries, ensures civilian control and observes the Three Non-Nuclear Principles as policy guidelines.^[10]

While space does not permit an extensive examination of this statement’s premises, it is notable that the mention of the ‘Exclusively Defense-Oriented Policy’ above comes at a time when many analysts share the view that the acquisition by the Japanese armed forces of platforms such as hypersonic glide vehicles and Tomahawk cruise missiles demonstrates their emergence as an offensive force rather than a purely defensive one.^[11] Moreover, the continued reference to the Three Non-Nuclear Principles sits uneasily alongside statements by Koizumi and Takaichi that seem to indicate a desire not to be constrained by them.^[12]

In response to the changing security environment and in adherence to the above-mentioned statement, Japan plans to undertake ‘a new way of warfare’, which essentially seeks to integrate modern forms of warfare, such as cyber, cognitive and electromagnetic warfare, into the traditional order of battle.^[13] As such, Japanese strategy now aims to integrate technological advancements such as mass drone warfare and AI-powered targeted strikes into traditional combat. To fulfil this objective, it seeks to build sustainable domestic procurement pipelines for essential components. It also seeks to prepare for long-drawn battles of attrition where superior supply chains could make the decisive difference in situations of total or partial denial of outside assistance.

Ways to Achieve Strategic Security

The subsequent parts of the document outline three interconnected tracks for Japan’s near-term strategic planning. Part 3 details the first track, which involves building up ‘Japan’s own architecture for national defence’ alongside extensive use of ‘active diplomacy’ to maximise US involvement in Japan’s defence and build up ‘multilateral and multilayered defence cooperation and exchanges to realise FOIP’.^[14] Part 4 concerns the second track, the ‘reinforcement of…defence production and technological bases’ to create sustainable domestic supply chains that also facilitate foreign cooperation.^[15] Finally, Part 5 discusses the third track of ‘reinforcing the human resource base’ of the Japanese armed forces.^[16]

The first track carries forward the priorities first identified in the landmark three national security documents of 2022. In addition to developing a suite of advanced missile systems, Japan plans to deploy a host of enhanced interceptor systems. Coupled with enhancements in space domain awareness (SDA) and cybersecurity, the Air Self-Defence Forces, the service at the forefront of implementing these measures, will be renamed the Aerospace Self-Defence Forces. A host of cost-efficient, mass-produced uncrewed systems that can be easily manufactured and maintained will be deployed as part of the Synchronised, Hybrid, Integrated and Enhanced Littoral Defence (SHIELD) system by next year.^[17]

The emphasis on ‘active diplomacy’ is also consistent with Japan’s recent behaviour. Its engagement with India, Australia, and countries in Southeast Asia and Europe has been well noted. The language used to describe Japan’s security ally is interesting:

Japan will maintain its peace, security, and independence centred on the Security Arrangements with the world’s dominant military power, the U.S., with which it shares basic values such as democracy, respect for human rights, the rule of law, and a capitalist economy, as well as interests in maintaining the peace and security of the world; and has strong economic ties.^[18]

The turn of phrase, ‘the world’s dominant military power’, may be intended as a form of implied warning to regional challengers (as well as an emollient for Washington). However, the formulation also raises a more troubling possibility: Japan may either be choosing to make explicit what it already recognises, or cherry-picking the lessons from the Ukraine and Iran conflicts. Firstly, as Iran clearly demonstrates, US military supremacy is no longer self-evident. Secondly, as both Iran and Ukraine have demonstrated, being a military superpower is no guarantee against being trapped in a quagmire of one’s own making despite expending multimillion-dollar weapon systems against a smaller but more determined enemy fighting on its own turf.^[19]

The buildup of a strong defence-industrial base in Japan, the second track, is deeply intertwined with the discussion above. The white paper argues for the importance of a self-reliant indigenous defence manufacturing base as the sine qua non of ‘achiev[ing] uniquely Japanese new ways of warfare’.^[20] There is also some discussion of joint development and production with trusted partners, accompanied by a map of key initiatives, such as the Global Combat Air Program, undertaken in conjunction with the United Kingdom and Italy.^[21] However, the overall impression is of a search for the maximum possible extent of autonomy.

Conversely, the use of arms exports to trusted countries to maintain collaboration and interoperability is also mentioned.^[22] Clearly, there is still some tension between the quest to achieve complete self-dependence in defence production and the goal of contributing to global security through Official Security Assistance and the newly-relaxed Three Principles on Arms Transfer. Greater indigenisation could hedge against US abandonment and strengthen Japan’s position within the alliance, but excessive mercantilism could frustrate partners seeking deeper defence-industrial cooperation. Unless Japan clarifies which sectors it intends to indigenise as a strategic priority, its broader intentions remain unclear.

Finally, Japan’s prioritisation of a human resource base is an appropriate, though somewhat belated, acknowledgement of the critical demographic crisis in the Self-Defence Forces. The steep shortfall in recruitment numbers, reflecting overall demographic decline, makes retaining existing service members vital. The white paper itself admits that as the JSDF continues to fall short of its target personnel levels, with the sufficiency rate standing at approximately 90%, securing human resources for uniformed…personnel remains a matter of critical importance.

It is important to note that this statistic immediately follows the claim that ‘the compensation of all JSDF personnel’ has been brought up ‘to the highest level in history’.^[23] Clearly, the tension between greater automation and retaining enough humans in the loop to sustain the defence buildup will be critical in years to come.

Part 5’s focus on intolerance towards harassment and promoting the Women, Peace and Security agenda has been a long time in the making, following revelations of widespread harassment of female personnel and the misogynistic cultures embedded within the SDF.^[24] The introduction of more lucrative terms for the Japanese equivalent of the Indian Armed Forces’ Short Service Commissions, as well as the widening of the scope for lateral entry of highly qualified personnel in specialised branches, is a welcome and impactful change.^[25] The white paper’s inclusion of language opening up new opportunities for international cross-training through SDF officers’ attendance at foreign Staff Colleges offers a new collaborative opportunity for partners such as India.^[26] New Delhi should therefore positively consider inviting selected SDF personnel to institutions such as the National Defence Academy.

Conclusion

Japan’s defence white paper, like doctrinal documents released by governments around the world, is both an elucidation of its perceptions of security challenges and an expression of the ideal security environment it seeks to create. As Prime Minister Takaichi attempts to bring Japan closer to the US while bolstering native defence capabilities, the 2026 edition clearly conveys both the prospects and challenges inherent in her quest. Much will now depend on the political will to carry forward unpopular changes, especially as the fiscal base of the defence budget remains the subject of active contestation. However, strategically, one can clearly observe in the white paper a Japan attempting to adapt to changed circumstances not only at the regional level, but also at the domestic and international levels.

^[1] “防衛白書「新しい戦い方」に対応 防衛関係の産業基盤を強化” [Defence White Paper: Responding to New Way of Warfare, Stregthening of Defence-Related Industrial Base], NHK, 4 August 2026.

^[2] “令和8年版 日本の防衛” [Reiwa 8 (2026) Edition: Defense of Japan], Ministry of Defense, Government of Japan, 4 August 2026. An English digest has also been made available as a separate pamphlet; “2026 Defense of Japan: Pamphlet”, Ministry of Defense, Government of Japan, 4 August 2026. Quotations throughout this article generally refer to the pamphlet, though in places where it does not provide clarity or elucidation, the main text is referred to.

^[3] “2026 Defense of Japan: Pamphlet”, no. 2, p. 1.

^[4] Ibid.

^[5] Ibid., pp. 2–3.

^[6] Ibid., p. 3.

^[7] Ibid.

^[8] Ibid., p. 4.

^[9] “令和8年版 日本の防衛” [Reiwa 8 (2026) Edition: Defense of Japan], no. 2, p. 235.

^[10] “2026 Defense of Japan: Pamphlet”, no. 2, p. 5.

^[11] Ronny P. Sasmita, “Japan is No Longer Asia’s Defensive Power”, Asia Times, 18 August 2026.

^[12] “Japan Defense Minister Calls for Nuclear Debate Without Taboo”, NHK World News, 23 July 2026; “Takaichi Appears Concerned of Constrained U.S. Nuclear Deterrence Due to Japan’s Nonnuclear Principles”, The Japan News by the Yomiuri Shimbun, 7 August 2026.

^[13] “2026 Defense of Japan: Pamphlet”, no. 2, p. 4.

^[14] Ibid., pp. 7–10.

^[15] Ibid., pp. 12–15.

^[16] Ibid., pp. 16–19.

^[17] Ibid., p. 8.

^[18] Ibid., p. 9. Emphasis added.

^[19] Alex Kolbin, “Managed Instability: Why the Wars Against Iran and Ukraine Can Go On and On and On…”, Commentary, War on the Rocks, 19 August 2026.

^[20] “2026 Defense of Japan: Pamphlet”, no. 2, p. 13.

^[21] Ibid., p. 14.

^[22] Ibid., p. 10.

^[23] Ibid., p. 17.

^[24] Ibid., p. 19; Hitoshi Kawano, “Gender Mainstreaming in the Japan Self-Defense Forces”, Japanese Journal of Sociology, Vol. 33, No. 1, March 2024, pp. 42–57.

^[25] “2026 Defense of Japan: Pamphlet”, no. 2, p. 17.

^[26] Ibid., p. 18.