Japanese Prime Mini-ster Fumio Kishida is the first Japanese leader to attend a NATO summit meeting. With Chinese and North Kor-ean military expansion in mind, he hinted at the de-teriorating security environment in East Asia by stating that ‘Ukraine may be East Asia tomorrow’.
South Korean President Yoon Seok-yeol — also the first South Korean president to attend a NATO summit — sent a policy consultation delegation to Japan in April 2022 before assuming the presidency to stress the importance of bilateral cooperation on North Korea. This move undoubtedly contributed to the realisation of the first Japan–ROK–US trilateral summit in nearly five years, overcoming tensions that plagued the preceding administrations.
For US President Joe Biden, whose administration emphasised ‘expanded trilateral cooperation’ in its February 2022 Indo–Pacific Strategy Action Plan, such a compromise between its two Asian allies is a welcome sign for the future. But these diplomatic gestures are insufficient for effective Japan–ROK–US trilateral security cooperation.
The Japanese government is currently formulating its next National Security Strategy and the ruling Liberal Democratic Party (LDP) mentions in its policy recommendations the United States, Australia, India, ASEAN, EU, NATO and AUKUS in the chapter on the ‘Free and Open Indo–Pacific (FOIP) and strengthening cooperation with allies and like-minded countries.’
Yet security cooperation between South Korea, Japan and the United States is only mentioned briefly in the context of North Korea’s nuclear threat. South Korea is singularly mentioned when the document briefly touches on trilateral security cooperation. The LDP’s manifesto for the 2022 upper house election is even more vacant — its foreign and defence policy section does not mention South Korea at all.
Such an absence may suggest that the Japanese government, particularly the ruling LDP, are reluctant to deepen or publicly promote security cooperation with South Korea, even if they might understand the need for enhanced cooperation.
Many Japanese politicians point to historical and political issues — such as wartime labour — as the primary reason for this attitude among Japanese politicians. But there is also a history of often overlooked defence frictions that Was-hington cares less to mediate.
In 2018, the South Korean Navy refused the entry of Japan Maritime Self-Defence Force (JMS-DF) vessels at a fleet rev-iew ceremony because they were flying the Rising Sun flag — a war time relic wh-ich also happens to be an official flag of the JMSDF. This was an unusual reaction because JMSDF vessels had visited South Ko-rea more than 10 times in the past with the same flag.
The Ministry of Defence and the Japan Self-Defence Forces reacted by not inviting the ROK Navy to the 2019 JMSDF fleet review, stating that ‘relations between Japan and South Korea remain very difficult and the environment is not sufficiently conducive for inviting ROK naval vessels to the fleet review’.
In December 2018, a South Korean destroyer aimed a fire-control radar at a JMSDF P-1 patrol aircraft. Japan’s Ministry of Defence strongly urged its South Korean counterpart to acknowledge the act and prevent its recurrence, but South Korea remains silent over the issue.
In 2019, the South Korean government notified Japan that it would not renew the Japan–ROK General Security of Military Information Agreement (GSOMIA) — a legally binding agreement that facilitates the sharing of military intelligence between Seoul and Tokyo. Still, the South Korean government withheld its declaration of the agreement’s termination just before its expiration date, so it remains in a state of limbo.
Since these hostilities occurred under South Korea’s former president Moon Jae-in, one might have argued that a change of leadership in both countries would resolve these rifts. But strengthening defence cooperation between the Japanese Self-Defence Forces and the ROK military will be difficult without a clear resolution of these teething defence incidents. Indeed, when Japanese Defence Minister Nobuo Kishi met with the South Korean delegation in April 2022, he expressed hope that President Yoon’s leadership might resolve defence concerns with an explicit reference to the 2018 patrol aircraft incident.
Anti-Korean sentiment among the core supporters of the ruling LDP remains strong. The recent assassination of former Japanese prime minister Shinzo Abe might affect the domestic political dynamics in Japan for the worse. With the loss of Abe, a figure who kept the hard-line conservative faction within the LDP in check, there is a greater chance that Prime Minister Kishida will sacrifice trilateral security cooperation for his political survival despite understanding its importance.
Washington has been pushing for trilateral cooperation for a long time and may see positive signs in the latest progress between Tokyo and Seoul. But the United States must understand that major obstacles to effective trilateral security cooperation include deep-seated anti-Korean sentiment within the LDP and damaged trust between the Japanese forces and South Korean military.
If the United States believes that enhanced trilateral cooperation is essential for regional security, it should end its silence and start actively mediating defence issues between the two regional allies.