A Delicate Thaw: Japan and South Korea Navigate Troubled Waters with China’s Shadow Looms

TOKYO – For decades, the relationship between Japan and South Korea has been a geopolitical tightrope walk, buffeted by historical grievances and strategic anxieties. But a fragile détente, painstakingly built over the last few years, is now facing a new test: navigating a more assertive China while simultaneously grappling with internal political shifts and questions about the future of U.S. security commitments in the region. The recent meetings between Japanese Prime Minister Sanae Takaichi and South Korean President Lee Jae-myung, though initially met with skepticism, offer a glimmer of hope – and a potential blueprint for resilience in a rapidly changing Indo-Pacific.

From Trade Wars to Radar Locks: A History of Strain

The road to cooperation hasn’t been smooth. Just a few years ago, the relationship between Tokyo and Seoul was spiraling. In 2018, a reported incident involving a South Korean warship allegedly locking its radar onto a Japanese patrol plane ignited tensions. This was followed by escalating trade disputes in 2019, with Japan tightening export controls and Seoul threatening to suspend intelligence sharing – a critical component of regional security. These actions stemmed from deep-seated disagreements over Japan’s colonial past in Korea, a legacy that continues to cast a long shadow over bilateral relations.

The wounds run deep, centered around issues like the treatment of “comfort women” during World War II and disputes over wartime forced labor. South Korean courts have repeatedly challenged the 1965 bilateral settlement intended to resolve historical claims, leading to diplomatic friction and stalled progress. According to a Statista poll from 2023, only 28% of South Koreans view relations with Japan positively, highlighting the persistent public distrust.

China’s Coercive Diplomacy: A Catalyst for Change?

However, China’s growing influence in the region has acted as a powerful, if uncomfortable, catalyst for change. Beijing has increasingly employed coercive tactics – economic pressure, military posturing – to punish countries perceived as aligning too closely with the United States or challenging its interests. In November, China responded sharply to remarks by Prime Minister Takaichi suggesting potential Japanese military involvement in the event of a Chinese attack on Taiwan. The response included suspending seafood imports from Japan, canceling cultural events, and discouraging Chinese tourism. This playbook is familiar; similar measures were deployed against South Korea in 2016-17 after Seoul agreed to host the U.S. Terminal High Altitude Area Defense (THAAD) missile defense system.

This pressure has underscored the strategic imperative for closer cooperation between Japan and South Korea, particularly as concerns grow about the reliability of U.S. security guarantees under a potentially shifting geopolitical landscape. The Council on Foreign Relations notes that a stronger alliance between Tokyo and Seoul is vital for maintaining regional stability and deterring further Chinese aggression.

An Unlikely Alliance: Takaichi and Lee’s Potential

The current leaders, Prime Minister Takaichi and President Lee, represent seemingly opposing ends of the political spectrum. Takaichi, from the right wing of Japan’s Liberal Democratic Party, is known for her conservative views and willingness to challenge South Korea on historical issues. She’s a protégé of the late Shinzo Abe, whose revisionist stance on history often strained relations with Seoul. Lee, a progressive, traditionally favors engagement with North Korea and closer ties with China, and has been more vocal about addressing Japan’s colonial legacy.

Yet, this very divergence could be their strength. Experts suggest that a partnership forged between leaders with differing political bases can be more durable than one built on pre-existing ideological alignment. They argue that Takaichi and Lee are uniquely positioned to break the cycle of disruption that has plagued the Japanese-South Korean relationship. The need for pragmatic solutions, coupled with low expectations from their respective domestic audiences, could create space for meaningful progress.

Beyond History: Building a Future-Proof Partnership

The initial signals are encouraging. Despite initial apprehension from both sides, the October meeting between Takaichi and Lee at the Asia-Pacific Economic Cooperation (APEC) forum was surprisingly positive. Reports indicate a respectful exchange, with Takaichi even bowing to the South Korean flag – a gesture widely praised in South Korean media. President Lee reportedly told a domestic audience he was “no longer worried” about working with Takaichi.

Moving forward, cooperation in areas of mutual interest – such as technology, supply chain resilience, and regional security – will be crucial. Building on the momentum from previous agreements, including the historic Camp David joint statement in 2023, Japan and South Korea can explore deeper collaboration in fields like quantum computing, artificial intelligence, and biotechnology. Japan can also advocate for South Korea’s inclusion in key regional security frameworks, such as the Quad (Australia, India, Japan, and the United States) and the informal “Squad” (Australia, Japan, the Philippines, and the United States), to streamline partnership-building efforts and enhance collective security.

The path ahead will undoubtedly be challenging. Old grievances won’t disappear overnight, and the potential for diplomatic setbacks remains. But the convergence of strategic imperatives – a rising China, uncertainties about U.S. commitments, and the need for regional stability – creates a unique opportunity for Japan and South Korea to forge a more resilient and enduring partnership. The delicate thaw underway offers a glimmer of hope for a more secure and prosperous future in the Indo-Pacific.