Japan's Prime Minister Yoko Hamasaki Signals Nuclear Submarine Ambitions, Igniting Regional Tensions

First Public Acknowledgment: Nuclear Submarines on the Table

On December 23, during an interview with Japan’s Yomiuri Shimbun, Hamasaki addressed questions about strengthening Japan’s defense capabilities, specifically whether the country might acquire nuclear-powered submarines. “We will explore all necessary measures to enhance deterrence and response capabilities, and we will not exclude any options,” she said, according to reports from the outlet. This marked the first time Hamasaki had directly mentioned nuclear submarines in a media interview, a shift that follows a October agreement between her ruling Liberal Democratic Party (LDP) and the Japan Innovation Party (JIP) to advance the development of nuclear-powered submarines. The agreement, though vague, was widely interpreted as a step toward acquiring such vessels, which would represent a significant upgrade to Japan’s naval capabilities.

Hamasaki’s comments came as she attended a joint event with Kyodo News, where she emphasized the need to boost Japan’s “sustained combat capabilities.” She also announced plans to revise three key security documents: the National Security Strategy, the National Defense Strategy, and the Defense Buildup Plan, citing a “changed security environment” as the impetus. The revisions are expected to formalize Japan’s shift toward a more assertive defense posture, including potential investments in advanced weaponry.

Regional Backlash: Neighbors on High Alert

Hamasaki’s statements have triggered strong reactions from Japan’s neighbors, who view the prospect of nuclear submarines as a threat to regional stability. South Korea’s Maeil Business Newspaper noted that the comments would “spark strong backlash” both domestically and in surrounding countries, while Taiwan’s political commentator Yuan Juzheng (苑举正) warned that Japan’s “gambling and treacherous behavior” could target China. “If Japan acquires nuclear weapons, its spearhead will likely point directly at China—we must be vigilant and prevent this,” he said.

In China, Foreign Ministry spokesperson Lin Jian condemned recent statements from a PM office official who claimed Japan “should possess nuclear weapons,” calling them “shocking.” Atomic bomb victim groups in Nagasaki, including four organizations, issued a stern protest on December 24, criticizing the official’s remarks and linking them to Japan’s historical use of nuclear weapons. The groups emphasized that Japan’s post-war pacifist identity is at risk of being eroded by such rhetoric.

Historical Wounds: Japan's Nuclear Past and Present

The debate over nuclear submarines is deeply intertwined with Japan’s history as the only country to have suffered atomic bombings. On December 18, a high-ranking official in the PM’s office suggested Japan should “possess nuclear weapons,” a statement that drew widespread condemnation. The Nagasaki victims’ groups argued that such rhetoric ignores the trauma of the 1945 bombings and risks reviving militarism.

Hamasaki’s comments also come amid speculation that she may visit Yasukuni Shrine, a site that honors Japan’s war dead, including convicted war criminals. Multiple Japanese media outlets reported that she is considering a visit on December 26, a move that would further strain relations with China and South Korea, which view the shrine as a symbol of Japan’s unrepentant past.

Broader Security Overhaul: Revising Key Documents

Hamasaki’s push to revise Japan’s security strategies is part of a broader effort to adapt to what she calls a “changed security environment.” The revisions are expected to outline a more aggressive defense posture, including increased spending on advanced weaponry and a greater emphasis on “deterrence.” The move aligns with Japan’s recent efforts to strengthen ties with the United States and other regional allies, but it has also raised concerns about a potential arms race in East Asia.

Defense Minister Kono Taro (小泉进次郎) had previously hinted at the possibility of nuclear submarines, stating in November that “we should not exclude discussions” about such vessels. His comments, combined with Hamasaki’s, suggest a coordinated effort by Japan’s leadership to explore nuclear-powered submarines as a key component of its defense strategy.

Conclusion: Tensions and Trauma

Hamasaki’s statements on nuclear submarines represent a significant shift in Japan’s security policy, one that has reignited debates about the country’s role in East Asia and its commitment to pacifism. While Japan argues that the move is necessary to counter threats from North Korea and China, neighbors fear that it could destabilize the region and erode the post-war order. The historical context of Japan’s nuclear past adds another layer of complexity, as victim groups and regional powers warn against a return to militarism.

As Japan moves forward with its security overhaul, the international community will be watching closely. The decision to acquire nuclear submarines—or even to publicly discuss it—could have far-reaching implications for regional stability, and for Japan’s relationship with its neighbors. For now, Hamasaki’s words have served as a wake-up call, reminding the world that the scars of history are never far from the surface of contemporary politics.