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Beyond North Korea: The Japan-South Korea-US Trilateral in the Indo-Pacific

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Beyond North Korea: The Japan-South Korea-US Trilateral in the Indo-Pacific

The Japan-South Korea-U.S. mechanism is a crucial piece in the United States’ broad Indo-Pacific strategy.

Beyond North Korea: The Japan-South Korea-US Trilateral in the Indo-Pacific

U.S. Secretary of State Antony J. Blinken hosts a joint press availability with Japanese Foreign Minister Hayashi Yoshimasa and Republic of Korea Foreign Minister Chung Eui-yong in Honolulu, Hawaii, on February 12, 2022.

Credit: State Department photo by Ron Przysucha

On February 13, Japan, South Korea, and the United States held a foreign minister-level tripartite meeting in Hawai’i to further discuss and deliberate the growing nuclear threat posed by North Korea. After continued efforts to grow its nuclear and ballistic missile program in 2021, Pyongyang carried out seven missile tests in January 2022 alone – a significant acceleration in its testing and demonstration activities. These tests, according to a U.N. report, involved new short-range (and, in one case, intermediate-range) missiles “incorporating both ballistic and guidance technologies and using both solid and liquid propellants,” a hypersonic guiding warhead, and a maneuverable re-entry vehicle. Through the tests, the U.N. experts found that the North also demonstrated enhanced capabilities for “rapid deployment, wide mobility (including at sea), and improved resilience of its missile forces.”

In response to such provocative and “unlawful activities,” Japan, South Korea, and the United States came together to condemn North Korea’s missile launches and reaffirm their shared determination and approach.

The Japan-South Korea-U.S. trilateral, which evolved post-Cold War to contend with the threat of North Korea, has clearly become a fundamental pillar for security and stability in Northeast Asia. The trilateral is a key aspect of the U.S. security framework in the region, and both Japan and South Korea prominently feature in the U.S. Indo-Pacific policy.

How does the trilateral shape Washington’s outlook towards the Indo-Pacific region as a whole? Will its focus remain concentrated on the dangers of the North Korean nuclear weapons program, via mechanisms like its Trilateral Coordination Oversight Group, or will it look to become a stabilizing platform for alliance politics in the Indo-Pacific?

Japan and South Korea in the U.S. Regional Outlook

Although both Japan and South Korea are key cornerstones of the U.S. hub-and-spokes alliance system in the region, the deterioration of Japan-South Korea relations over historical grievances has been an obstacle for trilateral cooperation. The U.S. role in the region has therefore involved acting as a mediator between the two neighboring states, pushing for repair and rapprochement of Japan-South Korea ties to ensure continued functioning of the high-stakes trilateral alliance. One example of this is the U.S. role in negotiating the Japan-South Korean 2015 agreement to end the “comfort women” dispute (which refers to the roughly 200,000 Korean women forced into sexual slavery by the Japanese military during the World War II), which has long been a major point of contention in Japan-South Korea ties and could deepen the wedge between them.

With Japan and South Korea as arguably the United States’ two most important allies in the Indo-Pacific, it is no surprise that they feature in Washington’s new Indo-Pacific Strategy released in February 2022. The strategy seeks to direct more security resources and diplomatic efforts to the Indo-Pacific to counteract China and preserve the free and open Indo-Pacific, and hopes to achieve this largely through “strong and mutually reinforcing coalitions.” It specifically mentions that the U.S. hopes to deepens its individual alliances with Japan and South Korea, and that the U.S. “will also encourage our allies and partners to strengthen their ties with one another, particularly Japan and the ROK.” There is also a subsection focused on “expand[ing] U.S.-Japan and ROK cooperation,” which pledges to engage trilaterally over North Korea issues and also other priorities such as supply-chain resilience, infrastructure development and women’s empowerment. “Nearly every major Indo-Pacific challenge requires close cooperation among the United States’ allies and
partners, particularly Japan and the ROK,” the strategy states.

The Japan-South Korea-U.S. trilateral not only complements the U.S. strategy but has been identified as crucial to its achievement. Japan and South Korea have significant influence in the Indo-Pacific, and their cooperation will be needed in the areas where the United States is pushing for augmented action against China and North Korea.

The Trilateral: New Momentum in the Indo-Pacific?

Over the last few years, in response to the changing security situation in the Indo-Pacific, there has been serious momentum building for the Japan-South Korea-U.S. trilateral, which is re-centralizing it as a crucial security partnership. U.S. foreign policy and its attempts to promote multilateralism in the Indo-Pacific are one contributing factor, as are some efforts for engagement and deeper diplomatic ties between Tokyo and Seoul in the face of shared security threats. The security environment of the Indo-Pacific is a significant element contributing to recognizing the importance of the trilateral.

Therefore, while the trilateral remains especially necessary to maintain peace and security in Northeast Asia and counter the nuclear threat of North Korea, it is now recognized as an important mechanism for securing the whole Indo-Pacific region. The trilateral is a necessary framework to preserve the liberal democratic order and prevent democratic backsliding and authoritarianism that could destabilize the Indo-Pacific. The United States, alongside two of the most important democracies in the region, represent a significant mass of power in support of democracy to counter authoritarian and belligerent powers China and North Korea.

In a press conference with U.S. President Joe Biden, former Japanese Prime Minister Suga Yoshihide made it clear that trilateral cooperation is essential with regards to both North Korea and the overall peace and stability in the Indo-Pacific, and that South Korea must be involved for effective action in the region.

The Quad Narrative

Furthermore, as a crucial part of U.S. security strategy in the Indo-Pacific, the Japan-South Korea-U.S. trilateral can work closely with like-minded partners such as Australia and India, for instance through the Quad format, thus further strengthening this coalition of democracies.

The Fourth Quad Foreign Ministers Meeting, held on February 11 in Melbourne, culminated in a joint statement that complimented the objectives of the Japan-South Korea-U.S. trilateral by stressing that cooperation is more effective against “coercion” such as Chinese economic and military expansion. The Quad statement also condemned the recent North Korean missile launches. Moreover, following the Quad Summit, U.S. Secretary of State Antony Blinken said that while confrontation with China was not inevitable, there were real and widespread concerns over China’s increasingly aggressive behavior, and worries that situations like Ukraine and the Russia-China “no limits strategic partnership” could serve to embolden Beijing and destabilize the Indo-Pacific.

In this context, the Japan-South Korea-U.S. trilateral meeting complemented the Quad’s latest session, because it emphasized the same commitments for security against North Korea and China and further banded these states together as the major democracies of the Indo-Pacific to counter authoritarian threats.

The trilateral also complements the “Quad Plus” narrative – a more inclusive mini-lateral of like-minded countries committed to preserving the rules-based liberal international order and which has a multipolar view of the world. Japan is already a member of the Quad, and South Korea has been floated as a potential addition to make the group into “Quad Plus.” Increasingly, countries like China and North Korea are being constrained by the synergy of countries like Japan and South Korea and their opposing outlook. Their association with the United States in their trilateral and participation in the Quad Plus framework would be an extension of this and would make the overall influence more impactful.

Calibrating Seoul’s Lukewarm Indo-Pacific Outlook

The one drawback to more intense cooperation between the Japan-South Korea-U.S. trilateral and Indo-Pacific mechanisms like the Quad could be South Korea’s lukewarm approach toward the Indo-Pacific (including forums like the Quad). This outlook is rooted in Seoul’s balancing act diplomacy as it attempts to walk a fine line between the United States and China. Seoul is careful not to appear a part of any overtly anti-China framework, as South Korea is dependent on China both for its economic growth and for any meaningful engagement with Pyongyang on denuclearization (a priority under President Moon Jae-in).

However, Seoul’s viewpoint may change after the upcoming presidential elections in March 2022. The conservative presidential contender, Yoon Suk-yeol, for instance, has strongly criticized the Moon administration for being too pro-China. He has argued that Seoul cannot be partners with China while Beijing remains a key ally of North Korea – the South’s “main enemy” – and instead advocated for further deepening ties with Seoul’s primary security partner, the United States. Yoon has also expressed interest in improving Seoul’s ties with Tokyo, a prospect that looks more promising now considering newly-elected Japanese Prime Minister Kishida Fumio’s more “dovish” outlook vis-à-vis South Korea. Accordingly, the likelihood for greater collaborations between the Japan-South Korea-U.S. trilateral and the Quad (and the Quad Plus), and by extension South Korea’s greater turn toward the Indo-Pacific, in the future is immense.

Hence, to conclude, the Japan-South Korea-U.S. mechanism is a crucial piece in the United States’ broad Indo-Pacific strategy and it can, moving forward, play a consequential role in the security and stability of the region. Already a foremost framework in terms of coordinating action against North Korea’s increasingly aggressive actions, the trilateral must now respond to the traditional security challenges in the Indo-Pacific as a whole. The China issue is not entirely separate from North Korea. Beijing too has shown itself to be a nuclear power all too willing to use military action and economic coercion to its own benefit. Here, the Japan-South Korea-U.S. trilateral must take a long view and act as a stabilizing platform for alliance politics.

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