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PacNet #6A – A trilateral intelligence sharing accord between Japan, Korea and the United States: implications and challenges

January 22, 2015

Conventional wisdom has it that intelligence is only shared between countries with a close friendship, and that the extent of intelligence sharing reflects the strength of their military relationship. It was surprising, therefore, that a tri-national intelligence sharing accord between Korea and Japan was announced Dec. 29, with the US as an intermediary. Only junior defense officials were present, and there was no formal signing ceremony; the pact is limited to information about North Korean weapons of mass destruction (WMD), nuclear tests, and long-range missile launches. Nevertheless, the very agreement to create this ad hoc tri-national command and control system demonstrates that the will exists in both countries to transcend political differences and to establish effective means of communication. If this promising start is to be expanded, many implications and challenges must be addressed.

History vs. the rebalance

Given the threat from North Korea’s nuclear and missile programs, there is a strong incentive for South Korea and Japan to exchange intelligence between their militaries, but the historical legacies of the region have limited bilateral military cooperation. Korea remains critical of Japan’s attitudes and behavior, especially its perception of transgressions committed during its colonial rule over the Korean Peninsula from 1910 to 1945. Prime Minister Abe Shinzo’s administration has also sought to build domestic political support by promoting Japan’s territorial claim to Dokdo in the East Sea, which has undermined Korea’s willingness to engage in strategic-level cooperation with Japan and the US. Japanese revisionism was the main reason for the sudden cancellation of an earlier bilateral information-sharing scheme in 2012. Indeed, there has been no formal military accord between Korea and Japan, although Korea agreed to cooperate with the US in 1987 and Japan signed a similar deal with the US in 2007.

Within Korea there is significant public opposition to any military deal with Japan, but the need has grown more urgent now that North Korea is developing the capability to miniaturize its nuclear warheads so that they can be mounted onto intercontinental ballistic missiles such as the Taepodong-2 and KN-08, which have an estimated range of 10,000∼12,000 km. Such technologies pose a grave threat not only to Seoul, but also to Tokyo and Washington.

Since the US alliances with Japan and Korea are the centerpiece of the US military’s rebalance to Asia, the new tri-national intelligence exchange marks a significant step. In effect, Korea is joining an ad hoc tri-national joint task force command, which implies an essential unity of political objectives among Seoul, Tokyo, and Washington. Korea has been reluctant to cooperate too closely with a conservative Japanese administration that is unashamedly revisionist and has reinterpreted its collective self-defense stance. It has become necessary, however, for Korea to balance these issues against the advantages of tri-national military collaboration.

The new accord provides Seoul with important strategic benefits in improved regional security, so that political calculations must be put to one side to establish regular military interactions with Tokyo as part of an ad hoc joint force chain of command and control; this constitutes an indirect recognition by Korea of the need for operational and tactical cooperation with Japan.

A US-led MD framework?

The tri-national military intelligence agreement has sparked controversy in Korea and China, with some arguing that it allows Korea to join the US-led missile defense (MD) framework. This is anticipated to be far more capable than would be required to contain North Korea, and so is widely assumed to be targeting Russia, and, critically, China. Seoul has denied that the agreement entails participation in the US-Japan MD regime, pointing to the development of its indigenous low-tier Korean Air Missile Defense (KAMD) shield to counter North Korean missile attacks, insisting that this is sufficient for multilateral military cooperation.

Beijing is concerned about any reconciliation between Seoul and Tokyo that involves accepting Japan’s military capacity to mount countermeasures against Chinese missile attacks. Beijing is highly suspicious that any tri-national military cooperation represents a first step toward a US-led Command, Control, Communications, Computers and Intelligence (C4I) MD framework to manage threats from China. Politically, Seoul and Beijing have made common cause against Tokyo’s refusal to adequately apologize for Japanese misconduct during the first half of the 20th century. From the Chinese perspective, this tri-national intelligence sharing accord looks ominously like another element of what they perceive as a US policy to contain China.

Nevertheless, the initial Chinese reaction to the announcement of the accord was restrained: Beijing is going to wait and see what the agreement involves, particularly for Korea. Does it really entail a Korean commitment to a tri-national MD network? Or will Seoul be satisfied with KAMD, which detects missiles at the boost phase rather than at the cruise or terminal phases? Beijing doesn’t want to see Seoul become part of a US-led MD partnership, nor does it want the Korean government to pardon its former colonizer by accepting its reinterpretation of the role of Japanese Self-Defense forces together with the rearmament this implies.

Beijing and Seoul share serious concerns about the persistence of Japanese revisionism, allied as it is with extreme forms of nationalism, and the extent of Seoul’s involvement with the US-led MD framework is unclear. There are substantial financial implications for Seoul if it is required to build an intelligence, reconnaissance and surveillance (ISR) capability, such as sea-based X-band radar, to match the US-led MD network, so Korea still has questions about the viability of involvement with deeper US-led regional security arrangements. Thus, Beijing appears willing to tolerate Seoul’s decision to join in the arrangement, and to overlook, for now, the implications for the shared front against historical Japanese abuses. It seems clear, in any event, that the Chinese response will be political and diplomatic, rather than military.

Need for a C4I system and rules of engagement

Between Japan and the US there is a parallel chain of command; between Korea and the US there is an integrated combined chain of command. If these are to share a common operational picture, including the location, disposition, and movement of North Korean forces, some disparities must be reconciled. For instance, this new arrangement appears to involve not only the national leaderships, but also national military commanders. Moreover, functionally this accord will entail more than just a military dialogue: it implies creating a military networking system based on C4I technologies.

In the pursuit of coalition objectives, as supplemented by intelligence from electronic instrumentation, there is a clear requirement for a systemically and legally designated command and control function, to coordinate tri-national efforts to operate Terminal High-Attitude Area Defense (THAAD). To facilitate the coordination of forces from Japan, Korea, and the US, politically and military, a C4I system and clear rules of engagement (ROE) are indispensible. Mounting effective multinational military operations against rapidly developing WMD threats across the Korean Peninsula, which is less than 200 miles wide, will mean monitoring, tracking, and processing inputs from systems yet to be established, and this will obviously require a robust C4I system. Also, any tri-national operational chain of command will need close communication among the political leaderships, as well as a system for exchanging experienced people and intelligence. This must be supported by unambiguous rules of engagement, so that the multinational force commander can make effective use of available forces. In conclusion, the new tri-national military arrangement which intelligence sharing will make possible can only succeed by establishing common operational or situational pictures based on the real-time exchange of intelligence and tactical data.

Dr. Sukjoon Yoon (, a retired Navy Captain, is a senior research fellow in the Korea Institute for Maritime Strategy, and visiting professor of the Department of Defence Systems Engineering in Sejong University, Seoul, Korea.

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