Relations between Japan and South Korea have been rocky ever since the end of the Japanese colonial occupation of Korea in 1945. Image: iStock

A landmark agreement allowing the Japanese and South Korean militaries to share intelligence that had been set expire on Saturday has been extended by Seoul at the last moment.

South Korean President Moon Jae-in’s administration, engaged in a highly emotive historical/diplomatic/trade dispute with Japan, had bounced the rift into the security sphere when it announced in August that it would not renew GSOMIA – the General Sharing of Military Intelligence Agreement.

The termination of GSOMIA would have played directly into the hands of Pyongyang as the perfect outcome of North Korea’s gat geun (“hat strings”) tactic, which seeks to lever South Korea away from Japan. The importance of that tactic may be weighed from the fact that it was discussed in front of espionage operatives by no less a personality than North Korea’s founder, Kim Il Sung himself.

Why trilateralism matters

The South Korea-US alliance has defended the former against North Korea for almost 70 years. Separately, the US and Japan are also allies. While South Korea and Japan have no formal defense treaty, so technically are not allies, the two countries’ defense relations are nevertheless important.

Japan plays a crucial role in South Korea’s national defense. In case of contingency or war on the Korean Peninsula, Japan provides seven bases where forces and materials can be gathered before moving onward to Korea.

Beyond these bases, Japan, South Korea and the US produce strategic synergies. They also make a statement, representing liberal democratic freedoms in a region where they face off against China, North Korea and Russia.

North Korea understands the importance of this trilateral relationship. It wants to break it.

The biggest obstacle to Pyongyang’s control of the peninsula is the US military presence in South Korea, and Seoul’s alliance with Washington. Hence North Korea has made direct and indirect efforts to remove US troops from Korea and end the alliance.

For instance, North Korea has continuously demanded an “end of war” declaration and a “peace treaty,” which could lead to a split in the alliance and the withdrawal of the US forces from South Korea.

South of the Demilitarized Zone, too, there have long been calls to remove US troops by various leftist and pro-North Korea organizations. For example on November 18, “Citizens Sovereignty Solidarity,” while holding a march aiming to welcome Kim Jong Un to Seoul, also held up funeral symbols for US Forces in Korea, for the South Korea-US alliance, and for sanctions on North Korea.

Despite a current brouhaha revolving around the cost of US troops in Korea, the majority of the South Korean public has historically supported the alliance.

So what else can North Korea do? Focus on Japan.

It can weaken South Korea–Japan relations by promoting anti-Japan feelings among South Koreans. Those easy-to-ignite feelings are based on ever-simmering historical animosities related to Japan’s colonial rule of the peninsula from 1910-1945.

Kim Il Sung’s gat geun tactic

The gat is a hat Korean men wore during the Joseon Dynasty (1392-1910). It has a large brim with two strings under the chin that secure the hat in its place. According to state founder Kim Il Sung’s “gat geun tactic,” one string (geun) represents South Korea’s alliance with the US; the other string represents South Korea’s relations with Japan.

By cutting one string, the hat blows off. Thus by destroying South Korea’s relations with Japan, South Korea itself crumbles – that is how Kim describes the gat geun tactic.

Kim first used the term “gat geun tactic” in 1969, when he gave a speech at Kim Jong Il Political University, which trains espionage agents and operatives. Kim emphasized the tactic again in 1972 during a graduation ceremony at Kim Il Sung Political University, which trains political officers, who are later are assigned to monitor the North Korean military.

The late Hwang Jang Yop, the most senior North Korean figure to defect to South Korea and formerly a close associate of Kim, said that Pyongyang makes full use of the gat-geun tactic to weaken the South Korea-US alliance and Japan-South Korea relations as part of its “united front” tactics.

A reproduction of a traditional Korean interior scene – complete with a Korean gentleman wearing a gat. Photo: Wikipedia Commons

Moon’s mad maneuver

So why did Seoul’s Moon Jae-in administration announce that it would not renew the GSOMIA with Japan – especially when Moon went to Thailand in October to sign an intel-sharing agreement with that nation?

From the perspective of security vis-a-vis North Korea, it makes little sense to sign an intelligence-sharing pact with Thailand, but end the existing one with Japan.

Moon’s Blue House has tried to claim that the US understands South Korea’s decision to end GSOMIA with Japan, and National Assemblyman Lee Hae-chan of Moon’s Democratic Party of Korea said, “Even with no GSOMIA, [South Korea]-US alliance relations remain firm, and in fact are even more important.”

However, a number of US officials, using unusually blunt, public language, said there was no seeking of US understanding. Secretary of State Mike Pompeo expressed his “disappointment,” and the Pentagon expressed “strong concern.”

More recently, US Defense Secretary Mark Esper and US Ambassador to Korea Harry Harris have both made clear they strongly favor maintaining GSOMIA.

Some within South Korea are also wary of killing GSOMIA.

It has been reported that the Ministry of National Defense was against the Blue House decision. And a group known as Korea Retired Generals and Admirals Defending the Nation, or KORGADcondemned the “bungled GSOMIA decision and the undiplomatic behavior … deliberately perpetrated by the ill-motivated Moon administration, thus not reflecting the will of most South Korean people.”

Former senior foreign-service officers also made a public statement, referring to GSOMIA as an “indispensable fulcrum of the security cooperation between Korea, US and Japan.” They added, “As for our relations with Japan, our two states are now on the verge of belligerency after the Moon government violated or terminated the 1965 Claims Settlement Agreement, the 2015 Korea-Japan ‘Comfort Women’ Agreement, and most recently, the 2016 GSOMIA. The termination of GSOMIA and the violation of the Treaty on Basic Relations between the Republic of Korea and Japan will undoubtedly undermine the cooperative relations among Korea, the US and Japan, and cripple the Korea-US alliance.”

Both groups called for the Moon administration to renew GSOMIA.

Playing to China, playing to North Korea

Weakening South Korea’s relations with Japan suits both North Korea and China.

It falls fully in line with North Korea’s gat geun tactic. It is also in line with the “Three Nos” that Seoul unwisely promised Beijing in 2017: No further deployment of the US THAAD (Terminal High Altitude Area Defense) system; no further US missiles defenses on South Korean soil; and no trilateral security alliance among Japan, South Korea and the US.

Nixing GSOMIA would have benefited neither South Korea’s national security nor its national interest. South Korea should not fall prey to North Korea’s gat geun tactic by weakening ties with Japan. A trilateral, liberal democratic partnership of Japan, South Korea and the US should work together as a bedrock of regional security.

Fortunately, a fracture in that bedrock appears to have been avoided with the news that GSOMIA remains in play.

Dr Tara O is a Fellow at the Institute for Corean-American Studies (ICAS). She is the author of The Collapse of North Korea: Challenges, Planning and Geopolitics of Unification. She serves on the board of directors of the International Council on Korean Studies and was the editor-in-chief of its International Journal of Korean Studies. An air force veteran, her research areas include the Korean contingency and unification, US alliance, human rights in North Korea, North Korean defectors, and South Korean politics.

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