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[Research Report] The Political Divide in South Korea in the Face of North Korea's Coercion Strategy

Takeshi Watanabe (Senior Fellow, National Institute for Defense Studies)
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Research Group on 'Korean Peninsula' FY2022-# 5

"Research Reports" are compiled by participants in research groups set up at the Japan Institute of International Affairs, and are designed to disseminate, in a timely fashion, the content of presentations made at research group meetings or analyses of current affairs. The "Research Reports" represent their authors' views. In addition to these "Research Reports", individual research groups will publish "Research Bulletins" covering the full range of the group's research themes.

While most people can agree on a wish for peace, there are often arguments over who is disturbing the peace. It is not always the case that people unite against threatening outsiders. Even if a nation almost undeniably faces outside adversaries, a significant number of people could accuse their own armed forces and allies of entrapping them in a dangerous security situation.

The divisive nature of seeking peace is apparent in the politics of South Korea (Republic of Korea, or ROK). Former President Moon Jae-in stressed "the vestiges of pro-Japanese collaborators" within the ROK military as the reason for the lasting tensions on the peninsula, and he called for clearing them out for the sake of future peace.

Even after a change in administration, South Korea continues to confront a domestic situation in which one side considers the military's actions to be political attempts to increase tensions, which could impact security on the Korean Peninsula. This impact will not be apparent until North Korea (Democratic People's Republic of Korea, or DPRK) halts its numerous acts of intimidation. The side in South Korea that regards efforts to reinforce deterrence as political actions will likely argue that the nation must promise not to pursue certain alliance cooperation in order to seize an opportunity for talks.

North Korea has synchronized an escalation of tensions with ROK military actions such as the resumption of US-ROK combined exercises and the US-ROK-Japan trilateral cooperation. The stronger the impression North Korea creates that the military actions of the ROK and its alignment with the US and Japan have exacerbated the situation, the more South Koreans may consider the ROK military to be preventing opportunities for peace talks by aligning with the US and Japan for political objectives.

Even if the incumbent ROK government prefers to preserve the option of reinforcing the alliance further in talks with North Korea, the South Korean opposition's argument may encourage some Americans who want to lessen the US presence. The division of South Korea, with one side seeing the military as a political actor preventing peace, increases the chances for success of North Korea's coercive strategy.

The Rise and Fall of Massive Retaliation and the Kill Chain

The presidential transition from progressive Moon Jae-in to Yoon Suk-yeol allowed the military to reaffirm the strategy pursued under Moon's conservative predecessors. The reemergence of this military strategy began on April 1, 2022, shortly after the victory of the conservative Yoon in the presidential election. On that day, Suh Wook, former army chief of staff and the last defense minister of the Moon Jae-in administration, stated that the military was capable of launching precision strikes on the origin of any imminent missile attack and its command and support facilities. This was the "kill chain," preemptive strikes to eliminate imminent missile threats, and the ROK military had not openly discussed this strategy during the latter part of the progressive Moon administration.

After the launch of the Yoon administration, the newly-appointed defense minister and former vice chairman of the Joint Chiefs of Staff, Lee Jong-Sup, stressed that the ROK military had the capabilities to precisely strike not only the source of a missile launch but also "command and support facilities" in North Korea. This was a reconfirmation of the Korean Massive Punishment and Retaliation (KMPR) another strategy that the military had mostly refrained from publicly mentioning under the previous government.

The origins of the kill chain and the KMPR strategy can be traced back to the time of conservative President Lee Myung-Bak when North Korea shelled Yeonpyeong Island. After the shelling in 2010, the ROK military started developing a strategy of preemption and stronger retaliation vis-à-vis North Korea. During the next presidency of Park Geun-hye, who was also a conservative, the military introduced the concept of the "three-pronged system" that included the kill chain, KMPR and KAMD (Korea Air and Missile Defense).

President Park's progressive replacement Moon Jae-in did not openly oppose the three-pronged system. However, the military eventually stopped mentioning the three-pronged system in public, as the Moon administration focused on implementing the military agreement reached at the summit meeting with North Korean leader Kim Jong-un on September 19, 2018.

The progressive government probably viewed the military as a political organization that refused to go along with its demand for peace. On March 1, 2019, President Moon pressed the military to fully embrace the agreement with North Korea for wiping out "the vestiges of pro-Japanese collaborators".

According to the presidential address at that time, clearing out pro-Japanese vestiges was about erasing "the 38th parallel drawn through our minds." The 38th parallel is a political term used in South Korea to describe the North-South division (the Military Demarcation Line on the Korean Peninsula is not the 38th parallel, but only close to it). The president explained his meaning by saying that the pro-Japanese collaborators had suppressed "independence activists" even after the end of colonial rule and created an "ideological stigma" that had intensified confrontations with North Korea. The president also stressed the necessity of implementing the military agreement of 2018 by establishing a common fishing zone where ROK armed forces had clashed with North Korea.

The ROK military had not actively promoted the establishment of a common fishing zone until then, and President Moon increased the pressure on the military to follow his progressive policy by effectively labeling the military's attitude the pro-Japanese vestige. It was also in 2019, the same year as the presidential address, that the Moon administration changed its previous position that had allowed the military to retain the strategy of the three-pronged system. On January 10, 2019, the ROK defense ministry announced that it would be replacing the concept of the three-pronged system with the idea of building up capabilities for responding to "omnidirectional" threats from weapons of mass destruction. The omnidirectional idea expanded the range of targets rather than focusing on North Korea. Even while announcing its intent to replace the concept, the defense ministry avoided mentioning the kill chain, explaining only that KAMD and KMPR would be continued.

The kill chain was effectively dropped as a military strategy when the Moon administration intensified its efforts to realize the progressive version of peace with North Korea. The rise and fall of the kill chain reflect the competition between the armed forces that pursue the strategy targeting North Korea and the progressive political forces that insist that pro-Japanese ideologues remain behind such move.

North Korea's Coercive Strategy and the Division within South Korea

The political divide involving the military is likely the reason North Korea's coercive strategy targets the ROK military rather than South Korea as a whole. The effective coercer incentivizes its opponent to comply with its demands based on the understanding of the motivations of the target actors in responding to an escalating situation (Alexander George, The Limits of Coercive Strategy, Westview Press, 1994, pp.288-289). North Korea's actions were suitable for convincing South Koreans who believed that the military was a political apparatus against peace to oppose improving the posture of US-ROK forces and the trilateral alignment with the US and Japan.

A day after the ROK defense minister reconfirmed the kill chain strategy in April 2022, Pak Jong-chon, secretary of the Central Committee (CC) of the Worker's Party of Korea (WPK) and former chief of the General Staff of the Korean People's Army (KPA), warned that a preemptive attack by South Korea would lead North Korea to "mercilessly direct all its military force into destroying major targets in Seoul and the south Korean army". Furthermore, Kim Yo-jong, vice department director of the WPK CC and sister of Kim Jong-un, criticized the remarks about the kill-chain and stated on April 4 that, despite South Korea not being the North's principal enemy, the ROK military could become the target of North Korea's nuclear weapons if it opts for a preemptive attack.

North Korea clearly attributes the danger of a nuclear attack to the ROK military, a domestic agent rather than South Korea as a unified actor, by synchronizing its escalation with the resumption of calls by the ROK military for a strategy not overwhelmingly agreed upon in South Korea. According to the remarks of WPK secretary Pak, the reaffirmation of the kill chain reflected "the anti-DPRK confrontational frenzy" in the ROK armed forces, reflecting an arbitrary position instead of one born of professionalism concerned with the interests of the nation as a whole.

Targeting the ROK military is a coercive strategy that threatens to entrap South Koreans into nuclear warfighting unless they prevent the military from pursuing its own aims. In expressing the intentions behind a potential attack on the ROK armed forces, Secretary Pak mentioned Seoul, the capital city of South Korea. He said, "If the south Korean army engages in a dangerous military action as a preemptive strike against the DPRK," the KPA would destroy "major targets in Seoul and the south Korean army." Pak did not have to mention that the targets include facilities in highly populated areas in stressing the capabilities of eliminating the armed forces. By mentioning Seoul, Pak let people understand that targeting the ROK military was the prelude for harming the population of South Korea.

The above remarks were followed by a test of short-range missiles resembling Russian Iskander-Ms to "enhance efficiency in the operation of tactical nukes" (The Korean Central News Agency, May 29, 2017). North Korea attempted to incentivize the South Korean public to oppose the ROK military by making them fear entrapment into nuclear war. If these missiles have more capability for attacking the armed forces than previous missiles, North Korea can establish greater credibility that the nuclear destruction would extend to civilians in the cities nearby military targets.

"Pro-Japanese" National Defense and US-ROK Combined Exercises

The next target of North Korea was the Northern Limit Line (NLL), which the ROK military regarded as the maritime border with North Korea. Indeed, the NLL is about President Moon's agenda for eliminating pro-Japanese successors, and thus North Korea's actions are also consistent with the objective of expanding domestic opposition to the armed forces of South Korea in future.

According to the ROK Joint Chiefs of Staff (JCS), North Korea on November 2, 2022, launched ballistic missiles, one of which crossed the NLL and landed near the territorial waters of South Korea. The JCS denounced the missile launches as a violation of the North-South military agreement of September 2018. The Yoon administration's presidential office also stressed that North Korea had launched a missile violating the NLL for the first time since the division of Korea.

The accusations by the ROK military and the Yoon administration gave the impression it was the missile landings in the waters beyond the NLL that constituted a violation of the military agreement. However, the military agreement was violated not because the NLL was crossed, but because missiles were launched at sea in an area where the agreement had banned military activities such as missile launches.

The ROK military and the conservatives no doubt believe that the military agreement should have been based on the NLL as the border line. Even though the Democratic Party of Korea (DPK), the largest progressive party, accused North Korea of launching missiles over the NLL, the DPK's Moon administration did not focus on securing the status of the NLL that the military demanded. This caused friction between the armed forces and the progressive administration, ending in President Moon's accusation of pro-Japanese vestiges in the military.

During the negotiations, the ROK military set a condition for the peace zone, within which the agreement would ban military activities, to extend equally north and south of the NLL. In this case, the NLL would play the role of a base line defining the peace zone, and thus the agreement would have confirmed the NLL to be the de-facto border between the two Koreas. North Korea never accepted such a condition, which would support the South Korean military's claim on the legal status of the NLL.

The Moon administration prioritized signing the military agreement over confirming the status of the NLL as the maritime border. The water zone defined by the final agreement within which military activities were restricted did not contain equal areas on both sides of the NLL, instead including more area south of the NLL in the Yellow Sea where the two militaries have clashed several times.

However, the maritime zone in the agreement was not named a "peace zone." Despite it serving almost the same function as a peace zone, the agreed maritime zone officially remained unnamed. This allowed the ROK military to avoid officially recognizing a peace zone that dismissed the NLL as a base line.

The ROK military has never since actively pursued negotiations for the establishment of a peace zone and has unilaterally referred to the agreed-upon water area as a "buffer zone". The designation "buffer zone" gives the impression that the matter is over and that there are no matters left to be negotiated. While one of the objectives of the military agreement was to establish a peace zone, no such zone yet exists four years after the agreement was signed. The ROK military probably started using the name "buffer zone" to avoid the establishment of a peace zone.

The resistance of the military to the peace zone was likely behind President Moon's accusations of the armed forces not wiping out the pro-Japanese vestiges. One of the concrete demands addressed to the military in the address on March 1, 2019 was the call to realize "fishermen's hopes of catching a full haul," in other words, negotiating with North Korea on establishing a common fishing zone that would overlap with the peace zone, regardless of concerns from the military about the NLL.

The NLL is a major point of contention between the armed forces and South Korean liberals who consider the military a pro-Japanese apparatus that has escalated tensions with North Korea for political reasons. The presidential address calling for the pro-Japanese vestiges to be eliminated over the NLL came shortly after Moon's remarks demanding reform to both the prosecution service and the police agency, which, in his view, were successors to a coercive political system established under Japanese colonial rule and had to be reborn (February 15, 2019). The Moon administration generally accused the justice and security apparatuses of being swayed by pro-Japanese factions and underscored the military's confrontation with North Korea as evidence of this.

Wiping out unjust power lurking within the political system and forcing the military to retreat from its existing strategy of targeting North Korea were probably overlapping with each other in the basic ideology of the Moon administration.

It was on March 2, 2019, a day after the address against pro-Japanese elements, that the Moon administration announced "the end" of Key Resolve (KR) and Foal Eagle (FE), major exercises between the ROK military and the US, expressing hope that this would reduce tensions and continue the progress made in US-North Korea dialogue. As with the NLL, the argument of the Moon administration that the ROK military can promote dialogue and reduce tensions by stopping their military exercises with the US virtually blamed the failure to ease tensions on the ROK military.

In 2022, the ROK military resumed Vigilant Storm, another US-ROK combined exercise halted by the Moon administration (known at that time as Vigilant Ace). Timed to coincide with this exercise was the North Korean launch of a missile that fell into the waters south of the NLL. This action underlined the distinguishable position of the ROK military from other actors in South Korea, seeking to impress on South Koreans that the position of the ROK military, and not that of South Korea as a whole, was the cause of escalation.

The effects of North Korea's military actions intended to influence South Korea's politics have not yet become apparent. Nevertheless, over the long run, they can help bring about the re-emergence of a political structure in which the ROK military is accused of being a pro-Japanese apparatus that raises tensions with North Korea for unjust political reasons.

The political division over the military's responses to North Korea continues in South Korea. On October 7, 2022, Lee Jae-myung, President Yoon's electoral opponent and the incumbent leader of the Democratic Party of Korea, the governing party under the Moon administration, denounced the ROK navy's participation in trilateral ballistic missile defense exercises with the US and Japan as "pro-Japanese national defense." Lee's criticism indicated that he shared views with President Moon despite belonging to a different faction in the party. The trilateral naval exercise was a response to a series of intimidating missile launches by North Korea.


President Yoon Suk-yeol's remarks on who had prevented independence and disturbed the nation's peace contrasted with those of President Moon Jae-in. At the 2022 Liberation Day address (August 15), President Yoon said that the independence movement did not terminate in 1945 when the Empire of Japan collapsed because it included the process "of building a free and independent nation in the face of Communist aggression." He also stressed that it should not be forgotten that "those who fought the Communist invasion in defense of our freedom and democracy" were "independence activists," too.

In this case, North Korea is the adversary that prevents the nation from achieving its full independence. Accordingly, the military's role is to properly carry out a strategy targeting North Korea.

Conversely, from the viewpoint of President Moon's address on wiping out pro-Japanese elements, the strategy targeting North Korea has prevented complete independence. This was because the North-South confrontation was deliberately intensified by pro-Japanese collaborators to repress independence activists.

A deep political division remains in South Korean politics. If North Korea repeatedly insists that the ROK military is causing the escalation, it will reinforce the view in South Korea that the ROK armed forces, alongside together with the US and Japan aligning with them, are a political force opposed to peace. One nation in the US-Japan-ROK trilateral cooperation continues to exhibit a division that increases its vulnerability to coercive strategies by its adversary.

(This is an English translation of a Japanese paper originally published on February 10, 2023)