The Koreas

Japan-South Korea Cooperation: Strength in Unity, Danger in Division

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The Koreas | Diplomacy | East Asia

Japan-South Korea Cooperation: Strength in Unity, Danger in Division

Deepened trilateral cooperation between the U.S. and its two key East Asian allies is a positive development, but the fragility of Japanese and South Korean leadership underscores the importance of long-term reconciliation. 

Japan-South Korea Cooperation: Strength in Unity, Danger in Division

South Korean President Yoon Suk-yeol (left) and Japanese Prime Minister Kishida Fumio attend a joint press conference after their summit in Tokyo, Japan, Mar. 16, 2023.

Credit: Facebook / Prime Minister’s Office of Japan

To say that Japan-South Korea relations went through a rough patch in the late 2010s and early 2020s would be quite an understatement. From trade and territorial disputes, to the radar lock incident, the situation was made all the worse by ongoing historical disputes, which resurfaced with high-profile court cases. It seemed at one point almost inconceivable that the bilateral relationship would ever recover. 

This makes the seemingly rapid turnaround pulled off by the Kishida Fumio and Yoon Suk-yeoul administrations all the more impressive; within months of each taking office, the resumption of so-called shuttle diplomacy, the resolution of the Abe-Moon era trade disputes, and even trilateral summits including the United States were all on the table. In the wake of China’s continued military expansion, Russia’s renewed imperial aggression, and North Korea’s recurrent belligerence, these moves toward reconciliation are in the obvious interests of both Japan and South Korea. 

However, the seemingly miraculous ointment that has been used by the two leaders has some very large flies in it. 

Chief among these is the inherent unpopularity of both Kishida and Yoon; in a recent poll, Yoon sits at a 36.3 percent approval rating while the ongoing slush fund scandal has seen Kishida’s approval rating slip to just 26 percent. Even if these issues were to be overcome, outstanding historical issues still simmer, other fault lines such as the Dokdo/Takeshima dispute remain unresolved, and in any case it would be unreasonable to expect that years of acrimony could be washed away so quickly. 

An even greater issue is the potential for the eventual political successors to Kishida and Yoon to undo their work. Of the leading contenders to replace Kishida, at least two are members of Nippon Kaigi, which promotes the exact kind of historical revisionism to which South Korea is very sensitive, and the leadership of South Korea’s opposition Democratic Party has made plain it does not support Yoon’s Japan policy.  

Consequently, while seemingly positive at the moment, the foundation of this rapprochement is very much built on sand; if it is to last, more must be done by both Japan and South Korea to resolve outstanding issues. 

History, Reconciliation, and Shared Values

The United States has long screamed the question from the sidelines to Japan and South Korea: “Why can’t you two just get along?”

The answer is, of course, primarily historical. For all the proclamations of a “future-oriented relationship,” history remains a defining factor. South Korea’s liberal party, now in opposition, in particular continues to run on a platform that it perceives primarily as based around seeking justice from Japan for past historical issues, and some argue that this sometimes devolves into wider anti-Japanese sentiment.

Whether this is the case or not, the scale of sensitivity in South Korea cannot be overstated – the 2019 trade dispute, tied heavily to a dispute over compensation for wartime forced labor, led to a wide-scale boycott movement of Japanese products, even causing a 17.9 percent decline in travel to Japan. The former United States Ambassador to South Korea Harry Harris, of Japanese ancestry, even came under fire for a mustache that was perceived to bear a resemblance to those of colonial-era figures. For their part, Japanese politicians making historical revisionist statements or paying visits to Yasukuni Shrine have further stoked controversy. The legacy of the colonial period cannot be easily forgotten.

History is immutable, and reconciliation will not come easily or quickly. Yet it remains important to the long-term relationship and the interests of both nations to resolve these issues. The goal of this article is not to pronounce on which side should do more to resolve historical issues and to achieve reconciliation or to suggest means for the two to reconcile. However, as a practical acknowledgement of the nature of Japan-South Korea relations and the limits of what can be expected in terms of cooperation, it is important to raise this point. At the very least, it should tell us to not expect too much too quickly, and it highlights the potential dangers to any current bilateral or trilateral cooperation. If the issues of history are not dealt with, then a return to the acrimonious Abe-Moon era is far from off the cards, and such an outcome is only to the benefit of the shared adversaries of both Japan and South Korea. 

Despite these historical issues, Japanese and South Korean values on present day issues are in broad alignment. 

When Yoon proclaimed that South Korea and Japan shared universal values and pursued common interests, it was no mere soundbite. Both countries espouse similar values in their respective policy documents relating to areas such as overseas aid, defense, and foreign policy, emphasizing freedom and human rights. Both rank as leading democracies along with Taiwan and are important standard-bearers of democratic values in a region rife with autocracy. Both heavily value their relationships with the United States and support the preservation of a rules-based international order. 

These are shared ideals that can be built on; they are a solid foundation for an alliance not only of interests, but of values – values that both countries see as worth promoting and defending. The effective defense of these values demands a united response, and acrimony between two of the staunchest defenders of these values over historical issues is an abrogation of responsibility on the part of those charged with defending them. For the limits of Japan-South Korea cooperation to be fully broken, real, lasting solutions to the historical disputes between the two must be found and viewed as vital matters of national security. 

Unity and Shared Values as National Security

China, Russia and North Korea – nuclear-armed states with territorial ambitions, unstable governments, or both – represent three of the world’s most dangerous security challenges, and they are arguably becoming more closely aligned with each other. While I myself have argued that such alliances of narrow interest do not last compared to alliances built on values, these countries nonetheless present long-term threats in that they are each dangerous even on their own. Neither Japan nor South Korea alone has the strength to effectively deter or induce any of these, and only through the preservation of a friendly, united relationship can the objectives of either be fulfilled. 

Autocratic states have long tried to sow mutual division and hatred. In particular, China’s invitation to then-South Korean President Park Geun-hye to attend a military parade in Tiananmen Square in 2015 raised immediate alarm bells in Washington and Tokyo, and Beijing has attempted to weaponize the shared history of Japanese colonialism in its other interactions with South Korea. It also practices influence operations in South Korea, aimed at dividing society, and it would be little stretch to imagine that such influence operations may be used to undermine the Japan-South Korea relationship as well. Both Russia and North Korea also invest heavily in influence operations, and it can be expected that efforts to drive wedges between Japan, South Korea, and the United States will continue. 

These tactics, however, are only effective because policymakers have failed to resolve outstanding historical issues; without a pot to stir, it is inevitable that such efforts would decline in effectiveness. This is why the resolution of these issues is a vital matter of national security for both Japan and South Korea – creating a genuinely friendly and positive relationship is the best way to guard against those who would seek to wedge-drive. A change in leadership in Japan or South Korea would be little threat if future leaders were not faced with the imminent problem of historical disputes. 

Whether Pressure or Inducement, Unity is Key

As things stand, countries like North Korea can simply wait for a change in leadership to exploit division to their own ends. It is vital that this ability be taken away. Regardless of whether pressure or inducement is being pursued, the policy objectives of Japan and South Korea are more likely to be achieved with unity. Sanctions and deterrence are less effective with a weak link, and the inducement power of individual states is not strong enough to produce meaningful, long-term change so long as there is the chance that it will be undone later. Unity – real unity without exploitable fault lines – is key to both effectively inducing and pressuring. Again, if the pot is taken away, it can no longer be stirred by adversaries that only wish harm on both South Korea and Japan. 

A foundation of shared values is an important first step, and with the institutionalization of trilateral cooperation promoted by the Biden administration there is hope that at least some of the benefits of the Kishida-Yoon thaw will be lasting. Nonetheless, for the benefits of the rapprochement to be permanent, real, and lasting, then resolutions, however hard they may be, need to be found. Doing so is the only way to safeguard both Japanese and South Korean values and interests in the long-term.