New Japan-South Korea-US Trilateral a Test of Leadership

By Purnendra Jain, Emeritus Professor, Department of Asian Studies, University of Adelaide

The new Japan-South Korea-US trilateral framework is built on historically shaky foundations, writes Purnendra Jain. The question is whether it can survive future changes of leadership.

The leaders of Japan, South Korea, and the United States – meeting for the first time in a stand-alone format – created a new trilateral consultative framework in mid-August that set a new milestone of cooperation between the US and its two key allies in Asia. Previously President Joe Biden, Prime Minister Fumio Kishida, and President Yoon Suk-yeol had met on the sidelines of multilateral meetings – the ASEAN summit in Phnom Penh in November 2022 and the Hiroshima G-7 in May.

The prospects of such a trilateral began to unfold with a new president taking office in South Korea in May 2022. President Yoon holds a different view of the emerging geo-strategic environment in the region, and especially his country’s approach to Japan, from his immediate predecessor Moon Jae-in.

Given Japan and South Korea's long history of animosity, ongoing tensions, and deep mistrust, Biden’s choice of the US presidential country retreat Camp David as the meeting venue had a symbolic meaning. It was here that then-President Jimmy Carter in 1978 had brokered peace between Israel and Egypt.

The joint statement signed by Kishida, Yoon, and Biden called this development a ‘new era of trilateral partnership’ and a ‘hinge point of history’, as geo-political competition between China and the US intensifies, Russia’s military aggression against Ukraine continues with little signs of ending and North Korea’s nuclear sabre-rattling unsettles the region.

Not only does the summit statement set out the goals and objectives of this trilateral and pledges to establish a three-way hotline for crisis communications, but it also institutionalises the trilateral framework by declaring that the leaders, foreign ministers, defence ministers, and national security advisors of the three nations will meet annually. The three leaders also announced the launching of an annual Trilateral Indo-Pacific Dialogue to ‘coordinate implementation of our Indo-Pacific approaches and to continually identify new areas for common action’.

The agenda is wide-ranging. It encompasses technology cooperation, climate management, economic security, supply chain resilience, countering disinformation, upholding the rules-based order, securing peace and stability across the Taiwan Strait and denuclearisation of North Korea. Other minilateral and multilateral organisations such as the G-7 and the Quad share many of these concerns.

What distinguishes this trilateral from others is that it establishes mechanisms and institutions at its inception to coordinate and implement its goals and objectives between the three allies. It targets specific challenges in Northeast Asia such as North Korea’s nuclearisation and ‘the dangerous and aggressive behaviour’ of China.

Aware that allies are wary of abandonment, the United States declared its extended deterrence commitments to Japan and South Korea were ‘ironclad and backed by the full range of US capabilities’. The three leaders also announced they would conduct annual, multi-domain, trilateral exercises to enhance coordinated capabilities.

Why was this historic deal agreed now and what were the key drivers behind it?  How enduring will it be, and what challenges lie ahead?

The deal only became possible with a thaw in Japan-South Korea relations after the election of a new president in South Korea last year. Unlike his predecessors, Yoon took a conciliatory approach to Japan.

The two northeast Asian nations, although security allies of the US for a long time, have had a bitter and unpredictable history arising from Japan’s colonisation of the Korean peninsula (1910-1945). Despite the two nations signing a treaty in 1965 to normalise their relationship – and Japan agreeing to a lump sum payment as reparation for its colonisation – the relationship has remained tense.

The issues of compensation for ‘comfort women’ – forced Korean sex slaves for the Japanese military during the occupation – disputed territorial rights over the Takeshima/Dokdo islands, and Japan’s whitewashing of its colonial past in its history books have been constant irritations.

For its part, Japan believes it has done what it could to normalise the relationship legally and financially. Besides signing the 1965 treaty, Japan issued statements under the names of chief cabinet secretary Kono in 1993 and prime minister Murayama in 1995, offering remorse and apologies over colonial rule, aggression and war. But these have not assuaged the Korean public’s feelings and some top political leaders still voice negative views of Japan’s war-time behaviour.

Of all the issues, the treatment of comfort women has been the most corrosive. It appeared to be settled in a 2015 agreement between former leaders Shinzo Abe and Park Geun-hye. However, this issue flared again during the presidency of Moon Jae-in (2017-22).

Moon invalidated the 2015 agreement after a special task force he established pronounced it flawed. In 2018, the Supreme Court of South Korea ordered Japanese companies to compensate forced labourers, which Japan rejected outright sending the bilateral relationship into a downward spiral.

As President-elect, Yoon visited Japan in April 2022 signalling a reset in relations. Under Yoon, Seoul dropped demands for compensation from Japanese companies. South Korea and Japan went on to repair damaged economic ties.

It was this rapprochement – and Yoon’s analysis of the strategic environment - that gave impetus to the Camp David trilateral.

It is the increasing intensity of the China-US rivalry that lies at the heart of the trilateral and Yoon’s Japan diplomacy.  While Tokyo and Washington have expressed deep concerns about China’s military assertiveness and economic coercion, Seoul’s perspectives on China in recent years have been less confrontational. But South Korea’s views of China shifted with Yoon, leading Beijing to warn Seoul not to take a confrontational line and not to side with the US and Japan over Taiwan.

Although the three leaders stated their Camp David summit was not about China, China set the context of this summit. In their joint statement, China was called out for its unlawful maritime claims in the South China Sea. In a veiled swipe at China, the statement opposed ‘any unilateral attempts to change the status quo in the waters of the Indo-Pacific’. It also reaffirmed the ‘importance of peace and stability across the Taiwan Strait as an indispensable element of security and prosperity in the international community’. The leaders’ focus on economic security and cooperation in technology also indirectly targets China, which has often used trade and economic ties as a lever to achieve its political objectives.

The joint statement identified North Korea's nuclear and missile programs and its cyber threats as other major security concerns, although the three nations allow they remain ‘committed to re-establishing dialogue’ with Pyongyang.  The statement also affirmed the leaders’ commitment to supporting Ukraine against Russia’s military aggression, coordinated sanctions on Russia, and reduced dependency on Russian energy.

China was quick to denounce the trilateral, dubbing it a ‘mini-NATO’ or ‘Indo-Pacific NATO’. But it is not a security pact.

Rather, the new trilateral adds another piece to the network of minilateral frameworks with the US at the centre, such as the US-Japan-Australia trilateral, the Quad, and AUKUS. China, North Korea, and most recently Russia’s Ukraine war have acted as drivers of this minilateral proliferation.

The Japan-South Korea-US trilateral framework was only made possible because of the change of guard in South Korea’s leadership, the new president’s approach towards North Korea and China, and his views of Japan.

The longevity and effectiveness of it remains to be tested. It rests on fragile foundations. There is a history of failure in Japan and Korea's attempts at rapprochement.

The new warmth in the South Korea-Japan relationship, Tokyo and Seoul’s aligned views of China, and a currently similar approach to North Korea have led to a new architecture for Northeast Asia.

The big question is whether this coincidence of strategic outlook survives changes in leadership, especially in the US and South Korea. If Trump or a Trump-like leader returns to the White House, or four years down the road, Yoon’s successor returns to the stance taken by Moon on Japan and North Korea, the new framework may not endure.


Purnendra Jain is an emeritus professor in the Department of Asian Studies at the University of Adelaide.