Should Japan change its approach to North Korean denuclearization?

Like its predecessors, the Sanae Takaichi administration recognizes that Japan is experiencing a deteriorating security environment in Northeast Asia amid shifts in the international order. Japan faces mounting security challenges, including North Korea’s advancing nuclear and missile programs, closer military ties between Russia and North Korea, and strengthening military relations between China and Russia. In particular, expanding Russia-North Korea military ties—potentially involving troop deployments and technology transfers—poses a complex security threat that could enhance North Korea’s conventional and strategic capabilities. As noted in Japan’s 2025 Defense White Paper, these developments are increasingly linking Euro-Atlantic and Northeast Asian security dynamics.

Despite this worsening security environment, Japan’s approach to North Korea has shown little innovation. Since the inauguration of the Takaichi administration, Tokyo has sought to engage in dialogue with Pyongyang. However, these efforts have been unequivocally rebuffed. Two years after the failed bilateral contact in Mongolia in 2024, relations remain stalled, with little prospect for near-term improvement. While a potential resumption of U.S.-North Korea dialogue could create an opportunity to reopen talks, this too presents significant challenges. Simultaneously, declining Japan-China relations in the previous year have further complicated the Northeast Asian security environment.

In response, Japan has pursued a dual strategy toward the Korean Peninsula and Northeast Asia: enhancing integrated deterrence through the Japan-U.S. alliance and deepening cooperation with South Korea, while promoting multilayered trilateral security cooperation. In recent years, Japan has intensified its cooperation with South Korea, consistent with Japan’s policy of fostering collaboration among like-minded nations to promote a free and open Indo-Pacific region. Compared to the Shinzo Abe era, the Takaichi administration places greater emphasis on strengthening Japan-South Korea relations as a central piece of regional security cooperation.

Nevertheless, as Japan has expanded its deterrence capabilities and cooperation with Seoul and Washington, the denuclearization of North Korea remains at an impasse. This issue constitutes the most critical security concern for Japan. 

Japan’s unwavering commitment to North Korean denuclearization

Japan has demonstrated an unwavering commitment to the denuclearization of the Korean Peninsula. The Takaichi administration continues to uphold the Treaty on the Non-Proliferation of Nuclear Weapons and regards North Korea’s denuclearization as essential to nuclear non-proliferation in Northeast Asia. As Foreign Minister Toshimitsu Motegi stated in his February 2026 address to the National Diet, calling for the complete dismantling of North Korea’s nuclear development, the Takaichi administration, in alignment with its predecessors, categorically rejected North Korea’s nuclear program under any circumstances.

Building on this commitment, Japan has consistently pursued the complete denuclearization of the Korean Peninsula within the framework of Japan-U.S. and Japan-U.S.-South Korea cooperation. While the November 2022 Phnom Penh Statement broadened trilateral cooperation to include the promotion of a Free and Open Indo-Pacific, this cooperation has traditionally centered on deterring North Korea. Therefore, deterrence of North Korea remains the primary focus of this trilateral framework.

This commitment has been sustained even during the second Trump administration, with trilateral engagements, including foreign ministerial meetings, consistently reaffirming the shared commitment to the complete denuclearization of North Korea. The same objective was reiterated at both the Japan-South Korea summit and the Japan-South Korea defense ministers’ meeting in January 2026, underscoring the three countries’ enduring alignment. 

Shifting approaches to denuclearization

Despite official trilateral declarations for North Korea’s complete denuclearization, progress has stalled since the 2019 Hanoi summit. Moreover, since then, subtle differences have emerged among the three countries’ approaches to achieving North Korea’s denuclearization under the second Trump administration and the Lee Jae Myung administration. At the core of these differences lies a fundamental question: whether to recognize North Korea as a nuclear-armed state.

U.S. President Donald Trump has consistently described North Korea as a “sort of nuclear power,” and discussions within his administration have favored recognizing North Korea as a nuclear-armed state. Meanwhile, in September 2025, the Lee Jae Myung administration announced the “END” initiative, marking a shift away from the Yoon Suk Yeol administration’s policy of prioritizing denuclearization and instead emphasizing engagement, exchange, and normalization of inter-Korean relations.

Conversely, Japan has not sufficiently addressed the evolving U.S. and South Korean perspectives regarding North Korea’s denuclearization. Japan’s response to South Korea’s END initiative has been largely muted. In this context, Japan faces the imminent challenge of recalibrating its strategy should Washington and Seoul move toward a degree of acceptance of North Korea’s possession of nuclear weapons.

Certainly, for Japan, there is currently no room for flexibility on the question of North Korea’s nuclear weapons. The Takaichi administration continues to prioritize both the complete denuclearization of North Korea and the return of all abduction victims. Furthermore, even if Tokyo were to make concessions on the nuclear issue, North Korea’s persistent refusal to negotiate on the abduction issue would likely keep bilateral relations at a standstill and leave the underlying security threat unresolved. While it is conceivable that Japan could consider offering concessions on the nuclear issue in the hope of eliciting movement from Pyongyang on the abduction issue, such a strategy would entail using core national security interests as leverage. Such a decision would be complex, challenging, and politically sensitive.

It is also inevitable that the Takaichi administration—which is supported by conservative factions—would be criticized for perceived weakness toward North Korea if it were to pursue negotiations predicated on the recognition of North Korea’s nuclear arsenal. These domestic political constraints increase the difficulty of Japan aligning with the United States’ and South Korea’s evolving perspectives on North Korea’s nuclear status.

Consequently, Japan’s assessment of the strategic efficacy of complete, verifiable, and irreversible denuclearization in North Korea meaningfully diverges from those of the United States and South Korea, both in its external relations with North Korea and within its domestic political discourse. Under these conditions, Japan’s diplomatic efforts are expected to remain focused on securing an agreement for the complete denuclearization of North Korea, primarily through the frameworks of Japan-U.S.-South Korea and Japan-South Korea cooperation. 

Trilateral cooperation and alternative strategies for denuclearization

Japan’s approach to enhancing cooperation through the Japan-U.S. alliance and like-minded countries, such as South Korea, in response to security challenges, represents a desirable and steady policy. Particularly in light of the trajectory of U.S.-Japan-South Korea cooperation, it is imperative for Japan to resolutely strengthen trilateral security relations.

At the same time, Japan needs to prepare for possible shifts in U.S. and South Korean policies regarding North Korea’s denuclearization, especially as Pyongyang has already declared itself a nuclear-armed state amid escalating tensions in Northeast Asia. An overly rigid adherence to existing positions may result in more explicit policy divergences concerning North Korea, potentially undermining trilateral cooperation on the North Korean nuclear issue, as occurred in the 2000s. Given the complex regional geopolitical landscape that Japan finds itself in, such an outcome must be avoided at all costs.

Formulating an effective strategy for North Korean denuclearization requires confronting a fundamental dilemma: how to negotiate with a state counterpart that is unequivocally unwilling to relinquish its nuclear arsenal? In Japan, debate has begun to extend beyond strict adherence to non-proliferation principles to include consideration of whether recognizing North Korea as a “de facto” nuclear state could facilitate progress toward denuclearization. Although Japan cannot officially recognize North Korea’s possession of nuclear weapons under any circumstances, there is a growing need for flexible, pragmatic discussions on how to realistically mitigate threats and secure diplomatic and security interests.

Such discussions do not imply Japan’s abandonment of North Korea’s denuclearization. Rather, they highlight that Japan is now at a strategic juncture where it must consider the necessity of altering its strategic approach toward North Korea.