Advancing U.S.-Japan-ROK Trilateral Cooperation
A U.S. Perspective

Daniel Sneider
March 30, 2016

Daniel Sneider (Stanford University) analyzes the foundations and future of the trilateral relationship from a U.S. perspective, highlighting the critical role the United States has played in mediating tensions between South Korea and Japan.

Recent developments lend hope to the prospects for trilateral cooperation in Northeast Asia between the United States and its two principal security allies in the region, Japan and the Republic of Korea (ROK). Last December, the two neighboring states reached an agreement to settle one of the most neuralgic issues arising out of their wartime past, the treatment of the Korean women coerced into sexual service by the Japanese Imperial Army during the wartime era, the so-called “comfort women.” North Korea’s increasingly belligerent pursuit of nuclear and missile weapons, combined with China’s aggressive actions in the South China Sea, has reinforced a sense that South Korea and Japan share security threats.

It would be naive, however, to see this shared perception as anything other than a fragile step forward. The gaps in strategic understanding and in the readiness to confront the disagreements over history, which are deeply rooted in the politics of identity, remain daunting. The two sides’ security perceptions are hardly identical, dictated as they are by geography and, for South Koreans, by the unresolved Cold War division of the Korean Peninsula. Most importantly, the ability of South Korea and Japan to bridge these gaps without the help of the United States has been and remains limited.

The danger for U.S. policymakers is to believe that the history issues can indeed now be put aside in favor of a shared understanding of the strategic situation in the region. That assumption would be dangerous because it could lead South Korea and Japan to fail to take needed steps to reinforce the progress they have made and move ahead on both the security and history fronts to create the basis for genuine trilateral cooperation. In order to understand the U.S. role in the pursuit of trilateral cooperation and partnership in Northeast Asia, it is important to look at the historical process that led to this moment.

Trilateral Cooperation: A Historical Perspective

The construction of a trilateral partnership between the United States and its two allies in the region, Japan and the ROK, has long been a strategic goal of U.S. foreign policy. As the Korean War made clear to U.S. policymakers, our security commitments to the ROK and Japan are interlinked, both conceptually and operationally. The United States’ defense of South Korea depends on the infrastructure of U.S. bases and other rear-area support in Japan. And the Korean Peninsula is the de facto front line, the strategic buffer, for the security of Japan.

In the wake of the Korean War, the United States seriously explored the creation of a regional security structure that would parallel NATO and include elements of regional economic association. The goal of collective security was even enshrined in the U.S. bilateral treaties signed at the time, explicitly in the treaty with the ROK and implicitly with Japan. The then-secret minute to the U.S.-Japan Security Treaty allowed U.S. forces in Japan, nominally under the United Nations Command, to respond to an attack on South Korea without prior consultation with the government of Japan.

U.S. policymakers soon discovered, however, that what made sense in the minds of strategists foundered on the rocky realities of the region. Asian nationalism, particularly the still powerful mistrust of Japan and the opposition to any revival of a regional Japanese security role, was the most powerful obstacle. Also, the Japanese government was itself reluctant to take on a greater security role, preferring to outsource security to the United States while focusing on postwar economic reconstruction. The official Japanese interpretation of the constitutional prohibitions on the use of force, which were imposed by the United States, clearly ruled out any collective security agreement that went beyond a narrow definition of self-defense.

Early U.S. efforts to press Japan and the ROK to normalize relations and settle their outstanding issues from the war and Japanese colonial rule met resistance, and ROK-Japan talks to establish diplomatic relations went nowhere. As a 1954 report from the National Security Council frankly observed, “underlying this failure and the chronic tension between the two countries is the deeply ingrained Korean fear and suspicion of Japan, and the equally fundamental Japanese sense of superiority over the Koreans.”  [1]

Despite the abortive attempts to create a regional security structure in the wake of the Korean War, the United States persisted in efforts to bring its two allies together. The normalization of diplomatic relations between the ROK and Japan in 1965 was a milestone, accomplished thanks to the efforts of South Korean and Japanese leaders, but not without behind-the-scenes U.S. mediation. In 1999, in response to burgeoning North Korean missile and nuclear challenges, the United States set up the Trilateral Coordination and Oversight Group with Japan and the ROK to offer a united policy response. Also, with the encouragement of the U.S. military, South Korean and Japanese defense and military officials held consultations, albeit under the radar. When a bilateral agreement on intelligence sharing between the two states’ defense establishments stalled recently, the United States helped the sides transcend their differences by forging a trilateral agreement that was more politically palatable.

U.S. efforts to strengthen the trilateral relationship focused almost entirely on security cooperation, deliberately avoiding the issues of wartime and colonial history. U.S. policymakers tended to see wartime history problems as irritants that could be put aside in the expectation that they would diminish over time. Washington resisted calls for U.S. involvement, fearing that it would only end up being blamed by both sides for not supporting either. That said, U.S. officials did understand that history could not be completely ignored. At the time of normalization of relations, for example, South Korea demanded an explicit apology and reparations from Japan. The United States orchestrated a compromise by which Japan offered indirect compensation to South Korea in the form of economic aid and loans that were vital to its modernization.

Seoul’s military-led governments were largely content with this approach. There were, however, serious moments of ROK-Japan tension, such as after the attempted assassination of Park Chung-hee in 1974 by a North Korean resident of Japan, which again required informal U.S. mediation. But South Korea’s democratization in 1987 unleashed powerful civic forces that raised the visibility of painful historical issues, including Korean collaboration with Japanese colonial rule, the “comfort women” issue, and the territorial dispute over the rocky islets that South Koreans call Dokdo and Japanese call Takeshima. The legacy of Japanese colonial rule re-emerged in Korean life, from academia to politics.

During the 1990s, progress was made toward reconciliation on wartime and colonial history issues, without any U.S. role, largely due to political changes in both countries. In Japan, the conservative Liberal Democratic Party (LDP), which had resisted moves to confront these unresolved issues, lost power in 1993. It was only able to return to power the following year by aligning with its archrival, the Japan Socialist Party, and later formed the now-ruling coalition with the pacifist Komeito and other minor parties. The breakthrough Kono Statement, issued in 1993 after revelations by Japanese historians and the public emergence of Korean victims, acknowledged a Japanese official role in the coercion of women to provide sexual services to the Japanese Imperial Army. Even more important, the 1995 statement on the 50th anniversary of the war, issued by Socialist prime minister Tomiichi Murayama, ruling in coalition with the LDP, offered contrition for Japanese aggression and colonial rule.

In South Korea, the end of military rule in 1987 and the democratization of the political system had an enormous impact on the handling of wartime history issues. It had the effect of increasing attention on previously taboo issues such as Korean collaboration with the Japanese colonial regime and the failure of Park Chung-hee’s government to press Japan for reparations for wartime crimes. Later in 1998 and again in 2003, progressive governments assumed power, led respectively by Kim Dae-jung and Roh Moo-hyun. They were supported by most civil-society activists on history issues and were better positioned to find avenues for reconciliation. Kim did so at the time of his 1998 visit to Japan, accepting Japanese apologies for the war and forming a joint commission of historians to examine the past. The two governments also attempted to resolve the “comfort women” issue in the mid-1990s with the formation of the Asian Women’s Fund, but it failed due to the opposition of South Korean civil society.

The progress stalled, however, and was even rolled back during the next decade. The return of conservative rule in Japan brought into power governments that sought to effectively overturn the Kono Statement and revise the Murayama apology. Meanwhile, subsequent South Korean governments found it hard to resist the temptation to play the card of anti-Japanese nationalism, particularly when popularity waned in the last years of a presidential administration. There was a limited opening to improve relations at the beginning of the Democratic Party of Japan’s rule in 2009, but ultimately such efforts also foundered. The bilateral relationship took a sharp downward turn during the administrations of President Lee Myung-bak and Prime Minister Yoshihiko Noda and deepened under their successors. The two sides’ inability to hold a bilateral summit for more than three years was unprecedented in the post-normalization period.

The December 2015 agreement on “comfort women” was the product of at least four years of on-and-off negotiations. The agreement owes much credit to the political determination of President Park Geun-hye and Prime Minister Shinzo Abe to clear the path for compromise. Abe’s pained decision to issue a statement on the 70th anniversary of the end of World War II was a departure from his long-stated desire to roll back previous admissions of Japanese responsibility for war crimes and paved the way for the agreement.

The U.S. Role

The recent breakthrough in Japan-ROK relations was significant, but, as I have detailed elsewhere, these developments could not have been reached without the concerted pressure of the Obama administration. The pressure came after the president and senior U.S. officials had reached the conclusion that the breakdown in bilateral relations was undermining fundamental U.S. security interests.  [2]   The president repeatedly intervened, in public and in private, to argue to both governments that their shared security interests, and values, must supersede disputes over the past. This was evident when Vice President Joe Biden attempted to mediate a Park-Abe meeting in December 2013. The United States felt compelled to act after China’s declaration of an air defense identification zone in the East China Sea the previous month. But that attempt failed badly when Abe visited the Yasukuni Shrine to Japan’s war dead within a couple of weeks of Biden’s trip to the region, despite entreaties by the United States not to do so. President Obama then brokered a trilateral meeting of the leaders on the sidelines of the Nuclear Security Summit in The Hague in March 2014 and continued to push the U.S. case during his visits to both capitals the following month.

U.S. State Department officials were involved on the sidelines of the negotiations between ROK and Japanese foreign ministry officials that were conducted fitfully for the next year and a half. Both Abe and Park heard the U.S. message forcefully from Obama himself during their separate visits to Washington last year. Abe’s war anniversary statement seemed to reflect the U.S. message to dampen down confrontation over the wartime past and set the stage for a bilateral summit with South Korea on the sidelines of the ROK-Japan-China summit in Seoul in early November 2015 and the “comfort women” deal that followed at the end of the year.

Challenges to Cooperation and the Path Forward

The steps toward cooperation would seem to indicate that South Korea and Japan have moved closer to a shared strategic perception in line with that of their U.S. ally, and that there is some commitment to put history issues on a parallel track that will not undermine cooperation. But it would be premature to conclude that these issues have been put to rest.

Seoul fears that the Abe administration has merely set its obsession with reversing the postwar judgment on Japan temporarily to the side, mostly to please Washington. The recent efforts of the Japanese Ministry of Foreign Affairs to oppose any discussion of “comfort women” at the UN Human Rights Commission are seen as evidence of the lurking compulsion to suppress wartime issues. The December agreement has not been implemented, particularly the formation of a fund for compensation, and it is not yet clear whether Japan will insist on the removal of a statue erected to commemorate the women across the street from its embassy in Seoul. Japanese similarly mistrust South Korean officials and lobby in Washington to put the responsibility for failure on them. Both sides watch to see if the United States is still committed to pressing forward on these wartime issues.

There also remains a serious divergence between South Korean and Japanese strategic policies and threat perceptions. The two are bound by their alliance partnership with the United States, but their preoccupations are distinct. A widespread feeling exists among South Koreans that their country is caught between its largest trading partner, China, and its closest ally, the United States. Some talk about South Korea acting as a “bridge” between the two great powers.

The central issue for ROK security policy continues to be the division of the Korean Peninsula and the ongoing threat of war arising out of North Korean miscalculation or Pyongyang’s undiminished desire to reunify Korea under its command. One element of the ROK’s response to the North Korean threat is the obvious effort to drive a wedge between Pyongyang and its Chinese patrons (just as the North seeks to do the same between Seoul and Washington). All these counterbalancing forces combine to make the ROK reluctant to be drawn into an overt balancing strategy against China. Both progressive and conservative leaders in South Korea share this view.

For their part, conservative Japanese leaders and policymakers tend to view South Korea as a secondary concern. The North Korean missile test over Japanese territory in 1998 alarmed Japan, and the abduction of Japanese citizens by North Korea has been a prominent cause among conservatives. But there is little discussion of the importance of South Korea to the defense and security of Japan, except to try to justify the recent revision of the interpretation of the constitutional restrictions on collective self-defense. Rather, Tokyo is concerned with the impact of China’s economic and military power on Japan’s future. According to U.S. military and defense officials, Japanese discussions of the implementation of the Joint Defense Guidelines agreed to last year with the United States have focused entirely on how U.S. forces might come to Japan’s aid in the case of a Chinese challenge to disputed territories in the East China Sea. In contrast, U.S. defense planners are focused primarily on Japan’s potential role in the defense of the Korean Peninsula and only secondarily on its role in other potential conflict areas such as the Taiwan Strait and the South China Sea.

These gaps in strategic perception have been kept largely under the surface, including by U.S. defense and security planners, who emphasize shared interests and wish to avoid disrupting the tentative steps toward trilateral cooperation. These officials also are wary of being drawn into choosing sides between two U.S. allies. This caution is understandable but not helpful in the long run. An airing of differences is essential to real cooperation.

While the United States needs to continue to steer its allies toward a shared understanding of the security imperatives that would underpin trilateral cooperation, it is vital to lock in the progress made on wartime history. Either side’s backsliding on the “comfort women” agreement must be avoided, and the United States can also encourage further opportunities for all three countries to promote reconciliation, such as through student exchanges, the visits of leaders to wartime history sites, and exchanges among historians. Similarly, it is crucial to identify other areas for trilateral cooperation, such as the three high-tech–powered economies’ shared interest in the protection of intellectual property. If there is a lesson from the historical process that brought us to this moment, it is that such a partnership can only emerge as a product of political leadership and sustained attention.


[1] Cited in Daniel C. Sneider, “The United States and Northeast Asia: The Cold War Legacy,” in Cross Currents: Regionalism and Nationalism in Northeast Asia, ed. Gi-Wook Shin and Daniel C. Sneider (Stanford: Walter H. Shorenstein Asia-Pacific Research Center Books, 2007), 269.

[2] Daniel Sneider, “Behind the Comfort Women Agreement,” Tokyo Business Today, January 10, 2016,

Daniel Sneider is the Associate Director for Research of the Shorenstein Asia-Pacific Research Center at Stanford University.

This brief reflects a U.S perspective on the U.S.-Japan-ROK trilateral relationship and was produced with support from the Korea Foundation and the Japan–United States Friendship Commission.