South Korea's recent decision to terminate a military intelligence-sharing pact with Japan was feared to only benefit North Korea and other regional military powers such as China and Russia, according to some experts and diplomatic sources.

James Schoff, a senior fellow at the Carnegie Endowment for International Peace, a Washington-based think tank, said Pyongyang is expected to "be confident" that the unity among Japan, South Korea and the United States, as well as the U.S. missile defense in the region are "not so strong."

"It's possible that North Korea feels relieved and refrains from provocative actions, or that it tries to separate Japan and South Korea," which are the two U.S. allies in Northeast Asia, Schoff said.

(Chinese President Xi Jinping (L) and North Korean leader Kim Jong Un)

Yun Duk Min, a professor at Hankuk University of Foreign Studies, said the end of the General Security of Military Information Agreement or GSOMIA would not only benefit North Korea but also China, which has been engaged in an escalating trade war with the United States.

A Japanese diplomatic source said it is difficult to determine whether Japan or South Korea would suffer bigger damage from the scrapping of the GSOMIA, but North Korea will surely gain advantage from the weakened three-way security cooperation.

Japan, South Korea and the United States have different strength in gathering intelligence on security fields, which makes their information sharing more meaningful.

Washington is good at using military satellites and reconnaissance planes, while Tokyo excels at signals intelligence and Seoul is superior in human intelligence.

A senior Japanese Defense Ministry official said it is "easier for the South Korean military to obtain much information in case of (Pyongyang's) missile firing due to its geographical proximity."

Another source from Japan's Self-Defense Forces said intelligence brought by Seoul is important for both Japan and the United States as South Korea leads intelligence gathering activities in the U.S.-South Korea combined forces through its ground radar networks, which cannot be covered by Japan's radar system.

Pyon Jin Il, editor-in-chief of the Korean affairs journal Korea Report, said the termination of the pact could lead to the resumption of inter-Korean dialogue and deal a serious blow to Japan, because Tokyo will be able to obtain information on North Korea only through the United States.

(Combined file photo shows James Schoff (L) and Yun Duk Min)

A senior SDF official also expressed concern that the Japanese government will become unable to obtain information which South Korea gets by interviewing North Korean defectors.

"That can influence the issue of Japanese nationals abducted" by North Korea in the 1970s and 1980s, the official said.

The GSOMIA was signed by Tokyo and Seoul in November 2016, and had been automatically renewed every year.

But amid an escalating bilateral row over wartime history and trade policy, South Korea on Friday officially informed Japan of its decision to terminate the pact a day before the deadline for either party to notify its intention to scrap the accord, which was set 90 days before its expiration on Nov. 23.

The agreement obliges the two East Asian countries to protect their shared military secrets, with the aim of preventing them from leaking to any third party. Japan has similar bilateral agreements with its closest ally, the United States, as well as France, Australia and the North Atlantic Treaty Organization.

The GSOMIA has been beneficial for the nations facing Pyongyang's threats as it allows them to communicate with each other swiftly in case North Korea fires missiles.

But the pact had met fierce public opposition in South Korea originating from Japan's past colonial rule of the Korean Peninsula.

Some experts say the impact from the termination of the GSOMIA would not be so serious, given that the two nations have been increasingly integrated with U.S. forces, respectively, and that the two countries can effectively continue sharing military intelligence through the United States.

Kim Young Jun, a professor at the Korean National Defense University in South Korea, pointed out that there are "only 20 to 30 cases (of intelligence) shared under the GSOMIA since its realization."

"The GSOMIA has a symbolic meaning of the trilateral security ties (among the United States, Japan and South Korea) but its termination would only have little substantial impact," he said.

[Photo courtesy of Korea Media]

Hirotaka Yamashita, a former high-ranking official of Japan's Ground Self-Defense Force, also said Japan's national defense would not be affected much by the lapse of the GSOMIA as Tokyo can obtain information on North Korean missile launches through data from U.S. early warning satellites.

Toshiyuki Ito, a former vice admiral at Japan's Maritime Self-Defense Force and current professor at Kanazawa Institute of Technology's Toranomon Graduate School, said South Korea would face bigger damage than Japan as it will not be able to easily obtain intelligence and analysis on North Korean missiles from the SDF.

Until the GSOMIA between Japan and South Korea came into effect, the United States had separately processed military secrets and provided them to the two Asian allies, Ito said.

"Secrets received by Japan were of better quality and larger in volume. That's because Washington was cautious about their leakage from the South Korean side," he said. Therefore, South Korea yearned for intelligence from Japan under the GSOMIA, while Tokyo received almost no military secrets from Seoul, he added.

Seoul also valued image analysis using Japanese intelligence satellites, with a South Korean diplomatic source saying that U.S. reconnaissance satellites do not always focus on North Korea.

A diplomatic source said the United States would be most troubled by the scrapping of the GSOMIA, because a U.S. government source has said the trilateral security cooperation holds the key to Washington's strategy in Northeast Asia.

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