By Sangbo Park
The Republic of Korea (ROK) and Japan signed a General Security of Military Information Agreement (GSOMIA) on November 23. It is hoped that this bilateral security agreement will play a crucial role in efforts to contain North Korea’s severe provocations.
From the perspective of South Korea’s national defense, sharing sensitive information with Japan’s Self-Defense Force (SDF) makes sense. As North Korea threatens South Korea by developing its nuclear arsenal and submarine-launched ballistic missile, Japanese advanced intelligence and anti-submarine warfare capabilities would allow South Korea to detect North Korea’s provocations promptly, and directly sharing military intelligence with Japan, rather than having to go through the U.S., will be more efficient. Moreover, it will also facilitate the U.S. sharing intelligence more efficiently with both Korea and Japan. But even more importantly, the GSOMIA contributes to cementing the U.S. alliance structure in Northeast Asia by putting in place an institutional mechanism for defense cooperation, providing the U.S. a framework necessary to stabilize the security environment in Northeast Asia.
The merit of a Japan-ROK GSOMIA for Japan is also clear. Prior to the agreement, South Korea had signed a GSOMIA with 32 countries and NATO. Japan had them with only six countries including the U.S. In other words, Japan signing one with the ROK clearly demonstrates that it considers this relationship strategically important. By cementing the institutional mechanism of U.S.-Japan-ROK trilateral cooperation through signing the GSOMIA, this will safeguard the close security cooperation regardless of power transitions in both the U.S. and South Korea.
For the U.S., as well, the Japan-ROK GSOMIA is an important development. Over the years, the U.S. has played a critical role as a stabilizer of regional security as well as the security guarantor for the two countries in Northeast Asia through its bilateral alliances with Japan and South Korea. Particularly in recent years, given the Obama administration’s “rebalance to the Asia Pacific” initiative and North Korea’s continuous provocations, all three countries clearly recognized the importance of trilateral cooperation and pledged to strengthen military cooperation, which was most vividly demonstrated via a joint missile drill in June. However, Washington has had difficulty building a deeper ties among the three countries, primarily due to Tokyo and Seoul having had years of strained relations over historical issues — including comfort women — and disagreements over territorial issues. The Japan-ROK GSOMIA would give a much needed boost to U.S. efforts to strengthen U.S.-Japan-ROK trilateral security cooperation to counter North Korea’s provocation and other security challenges in Northeast Asia.
The two governments made their first attempt to sign such an agreement in 2012 under then-President Lee Myung-bak’s administration. However, facing strong criticism and resistance both from opposition parties and the public when the government brought the GSOMIA before the National Assembly, President Lee was obliged to forgo it. Park Geun-hye, his successor, was reluctant to try again and instead attempted to strengthen ties with China, including by attending a military parade in Beijing in 2015 to celebrate the end of World War II.
Park, however, moved toward US-Japan-ROK trilateral cooperation following North Korea’s resumption of nuclear tests and China’s equivocal attitude on sanctions. Her sense of urgency to improve ties with Japan also encouraged her government to reach an agreement with Japan over comfort women in December 2015, which invited strong domestic opposition in ROK despite an enthusiastic welcome from the US. The GSOMIA, signed less than a year later, is another step that demonstrates the Park administration’s strong desire to continue to improve ties with Japan.
The GSOMIA, however, is already being criticized heavily in the ROK. There is no doubt that it was an unpopular move — a public opinion poll by Gallup Korea indicates that close to 60% oppose the deal with Japan, while only about 30% approve. This is not only because of the persistent anti-Japanese sentiment in the country. Some South Koreans believe that Seoul has more intelligence on North Korea than Japan, particularly human intelligence. Furthermore, the Park administration has already made the decision to deploy the Terminal High Altitude Area Defense (THAAD) to enhance the existing missile defense against North Korean threats despite Beijing’s displeasure, which was also a controversial decision. According to an Asan Institute for Policy Studies poll, 71.8% of the people are concerned about China’s economic retaliation even though 53.6% of the people agree to the THAAD deployment. Critics argue that the GSOMIA would let Tokyo take advantage of the ROK’s intelligence on the developments inside North Korea while putting the ROK even more at odds with China, for a return that is too small to be worthwhile.

Source: Gallup Korea
It is also important to consider that President Park, who has been impeached, may have had her own reasons to direct the Minister of National Defense to sign the GSOMIA with Japan. Her approval rating was only 5% on the brink of the impeachment. Given the fact that any bilateral agreement between Korea and Japan is hardly likely to be reached under a progressive administration, Park might be determined to augment trilateral cooperation not only for the U.S. and Japan, but also for the sake of her own legacy.
Still, signed amid public indignation over President Park’s scandal and the high level of opposition to closer defense ties with Japan, the Japan-ROK GSOMIA will present a new ROK president with a difficult choice of whether to sustain the agreement or whether to bend to public sentiment and scrap it at the expense of not only losing its military benefits, but also possibly facing a cooler relationship with the ROK’s most important ally, the United States.
____
Sangbo Park is an intern with the East Asia program at the Stimson Center and a fellow at the Asan Academy.
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By Sangbo Park
The Republic of Korea (ROK) and Japan signed a General Security of Military Information Agreement (GSOMIA) on November 23. It is hoped that this bilateral security agreement will play a crucial role in efforts to contain North Korea’s severe provocations.
From the perspective of South Korea’s national defense, sharing sensitive information with Japan’s Self-Defense Force (SDF) makes sense. As North Korea threatens South Korea by developing its nuclear arsenal and submarine-launched ballistic missile, Japanese advanced intelligence and anti-submarine warfare capabilities would allow South Korea to detect North Korea’s provocations promptly, and directly sharing military intelligence with Japan, rather than having to go through the U.S., will be more efficient. Moreover, it will also facilitate the U.S. sharing intelligence more efficiently with both Korea and Japan. But even more importantly, the GSOMIA contributes to cementing the U.S. alliance structure in Northeast Asia by putting in place an institutional mechanism for defense cooperation, providing the U.S. a framework necessary to stabilize the security environment in Northeast Asia.
The merit of a Japan-ROK GSOMIA for Japan is also clear. Prior to the agreement, South Korea had signed a GSOMIA with 32 countries and NATO. Japan had them with only six countries including the U.S. In other words, Japan signing one with the ROK clearly demonstrates that it considers this relationship strategically important. By cementing the institutional mechanism of U.S.-Japan-ROK trilateral cooperation through signing the GSOMIA, this will safeguard the close security cooperation regardless of power transitions in both the U.S. and South Korea.
For the U.S., as well, the Japan-ROK GSOMIA is an important development. Over the years, the U.S. has played a critical role as a stabilizer of regional security as well as the security guarantor for the two countries in Northeast Asia through its bilateral alliances with Japan and South Korea. Particularly in recent years, given the Obama administration’s “rebalance to the Asia Pacific” initiative and North Korea’s continuous provocations, all three countries clearly recognized the importance of trilateral cooperation and pledged to strengthen military cooperation, which was most vividly demonstrated via a joint missile drill in June. However, Washington has had difficulty building a deeper ties among the three countries, primarily due to Tokyo and Seoul having had years of strained relations over historical issues — including comfort women — and disagreements over territorial issues. The Japan-ROK GSOMIA would give a much needed boost to U.S. efforts to strengthen U.S.-Japan-ROK trilateral security cooperation to counter North Korea’s provocation and other security challenges in Northeast Asia.
The two governments made their first attempt to sign such an agreement in 2012 under then-President Lee Myung-bak’s administration. However, facing strong criticism and resistance both from opposition parties and the public when the government brought the GSOMIA before the National Assembly, President Lee was obliged to forgo it. Park Geun-hye, his successor, was reluctant to try again and instead attempted to strengthen ties with China, including by attending a military parade in Beijing in 2015 to celebrate the end of World War II.
Park, however, moved toward US-Japan-ROK trilateral cooperation following North Korea’s resumption of nuclear tests and China’s equivocal attitude on sanctions. Her sense of urgency to improve ties with Japan also encouraged her government to reach an agreement with Japan over comfort women in December 2015, which invited strong domestic opposition in ROK despite an enthusiastic welcome from the US. The GSOMIA, signed less than a year later, is another step that demonstrates the Park administration’s strong desire to continue to improve ties with Japan.
The GSOMIA, however, is already being criticized heavily in the ROK. There is no doubt that it was an unpopular move — a public opinion poll by Gallup Korea indicates that close to 60% oppose the deal with Japan, while only about 30% approve. This is not only because of the persistent anti-Japanese sentiment in the country. Some South Koreans believe that Seoul has more intelligence on North Korea than Japan, particularly human intelligence. Furthermore, the Park administration has already made the decision to deploy the Terminal High Altitude Area Defense (THAAD) to enhance the existing missile defense against North Korean threats despite Beijing’s displeasure, which was also a controversial decision. According to an Asan Institute for Policy Studies poll, 71.8% of the people are concerned about China’s economic retaliation even though 53.6% of the people agree to the THAAD deployment. Critics argue that the GSOMIA would let Tokyo take advantage of the ROK’s intelligence on the developments inside North Korea while putting the ROK even more at odds with China, for a return that is too small to be worthwhile.
Source: Gallup Korea
It is also important to consider that President Park, who has been impeached, may have had her own reasons to direct the Minister of National Defense to sign the GSOMIA with Japan. Her approval rating was only 5% on the brink of the impeachment. Given the fact that any bilateral agreement between Korea and Japan is hardly likely to be reached under a progressive administration, Park might be determined to augment trilateral cooperation not only for the U.S. and Japan, but also for the sake of her own legacy.
Still, signed amid public indignation over President Park’s scandal and the high level of opposition to closer defense ties with Japan, the Japan-ROK GSOMIA will present a new ROK president with a difficult choice of whether to sustain the agreement or whether to bend to public sentiment and scrap it at the expense of not only losing its military benefits, but also possibly facing a cooler relationship with the ROK’s most important ally, the United States.
____
Sangbo Park is an intern with the East Asia program at the Stimson Center and a fellow at the Asan Academy.
Photo credit: U.S. Government Work via Flickr
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