Four Policy Tasks for Peaceful Coexistence on the  Korean Peninsula Under the Lee Jae Myung Administration

​

Bong-Geun Jun

jun2030@mofa.or.kr​

Visiting Research Fellow

Sejong Institute

1. Introduction

“How should the Korean Peninsula problem be addressed? It can never truly be resolved; it can only be managed.” Tim Marshall said this in his best-selling work, Prisoners of Geography (2016). Yet in the case of the Korean Peninsula, even management has proven difficult, let alone resolution. During the early post-Cold War years, South Korea enjoyed an overwhelmingly favorable policy environment against North Korea. Nevertheless, the long anticipated collapse or systemic transformation of the North Korean regime did not materialize. Instead, despite sustained and maximum sanctions and pressure, North Korea succeeded in not only securing regime survival but also acquiring nuclear weapons. In the post-post-Cold War period, the Korean Peninsula has increasingly fallen into what can be described as a “new Cold War trap,” characterized by intensified military confrontation between the two Koreas amid the broader phenomenon of “bloc formation in Northeast Asia.” Throughout the post Cold War era, South Korea remained absorbed in the vision of absorptive unification. Today, by contrast, it finds itself confronting persistent fears of a potential North Korean nuclear strike.

From the late 2010s onward, a sequence of four events unfolded in rapid succession, initiating a qualitative transformation in the security environment of Northeast Asia and the Korean Peninsula. These events gave rise to what can be described as a “new Cold War on the Korean Peninsula.” For North Korea, which throughout the post-Cold War period had remained under persistent conditions of regime and systemic crisis, this shift provided an opportunity to seek an exit from that predicament.

First, following the success of its self proclaimed “hydrogen bomb” test in September 2017 and the test launch of the Hwasong-15 intercontinental ballistic missile in November of the same year, North Korea declared the “completion of its state nuclear force.” Through this declaration, the regime freed itself from its longstanding fear of South Korea’s absorptive unification and from what it perceived as the threat of a “United States invasion and regime change.“

Second, beginning in the late 2010s, intensifying “competition between the United States and China” accompanied “the rise of China.” In this context, Beijing came to reassess the value of North Korea as a “strategic buffer state.“

Third, following the outbreak of the Russia-Ukraine war in February 2022, competition between the United States and Russia emerged. Against the backdrop of the war and renewed U.S.-Russia rivalry, a North Korea-Russia alliance was concluded in 2024. This development provided North Korea with a new avenue for both security and economic relief.

Fourth, the return of President Donald Trump accelerated the deinstitutionalization and deideologization of global politics while hastening the transition toward a multipolar system and an era of great power politics. The second Trump administration may acknowledge the existing reality of North Korea’s nuclear armament (without recognizing it as a “nuclear weapon state“), and may pursue a diplomatic normalization with North Korea, reminiscent of China’s equidistant diplomacy between the two Koreas.

Against this backdrop on the Korean Peninsula and in the broader international environment, North Korea abruptly abandoned its long standing national unification state line in early 2024. It redefined inter-Korean relations as “two hostile states,” and began to regard South Korea as an object of conquest, and went so far as to issue threats of nuclear attack. As competition among the United States and China, the United States and Russia, and China and Japan intensified across Northeast Asia, rivalry between the two Koreas has simultaneously escalated on the Korean Peninsula. As a result, the likelihood of military conflict, including the potential use of nuclear weapons, has increased markedly on the Korean Peninsula and in its surrounding region.

The return of President Donald Trump in January 2025 has placed the Korean Peninsula at a new crossroads. Trump’s return, coupled with his favorable disposition toward Kim Jong Un and the renewed possibility of a U.S.-North Korea summit, constitutes a variable capable of drawing a major inflection point in peninsular dynamics. During Trump’s first term, policy toward North Korea oscillated sharply between extreme coercion and engagement, producing dramatic swings in the security environment. With expectations growing that a second Trump administration may pursue a unilateral approach toward North Korea and seek a so called “small deal,” significant domestic controversy appears unavoidable.

Against this context, the following analysis assesses Kim Jong Un’s new national security policy that this paper names as “new-Cold War strategic initiative” for the post-post-Cold War era. It then identifies four priority tasks for the Lee Jae Myung government’s North Korea policy and outlines strategies aimed at countering these new security challenges.

2. Assessment of Kim Jong Un’s “New Cold War Strategy” in the Post-Post-Cold War Era

A. Sustained Expansion of North Korea’s Nuclear Capabilities: Intensifying Nuclear Threats and the Potential Elevation of Nuclear Status

Nuclear armament constitutes the core of Kim Jong Un’s national security strategy. Even after 2025, North Korea is expected to continue prioritizing the expansion of its nuclear deterrent as a core element of national security. To this end, it is likely to focus on increasing fissile material production and on the development and deployment of delivery systems (missiles, strategic submarines). At the Supreme People’s Assembly in September 2023, Kim Jong Un called for “the exponential expansion of nuclear weapons production, diversification of nuclear strike capabilities, and their operational deployment across multiple military services.” In September 2024, during a visit to a uranium enrichment facility, he directed “an increase in the number of centrifuges” and the early introduction of new centrifuge models to further accelerate the exponential growth of the nuclear arsenal. Accordingly, in 2025, North Korea is expected to accelerate efforts to “operationally deploy diversified nuclear strike capabilities across different branches of its armed forces.”

Following the failure of ROK-U.S. denuclearization diplomacy to halt North Korea’s nuclear development, pessimism regarding denuclearization and skepticism about the utility of nuclear diplomacy have become widespread in both Seoul and Washington. If, however, nuclear diplomacy were to be abandoned, and North Korea’s nuclear expansion left unchecked, what can we expect in 10 years? North Korea could possess approximately 150 nuclear warheads, approaching the nuclear arsenals of Israel, Pakistan, and India. Within a decade, North Korea could possess approximately 150 nuclear warheads, approaching the nuclear arsenals of Israel, Pakistan, and India. Moreover, over such a time horizon, North Korea could potentially move beyond its current status as an “illegitimate nuclear-armed state” and come to be tolerated as a de facto nuclear weapons state, alongside India, Pakistan, and Israel. Given the risks implied by such a future trajectory, it becomes imperative to actively consider a phased approach to denuclearization that begins with a freeze on North Korea’s nuclear program.

B. Institutionalizing “Two Hostile States on the Korean Peninsula” to Reject Absorptive Unification and External Diplomatic Intervention

As part of his new Cold War strategic framework, Kim Jong Un has sought to fundamentally eliminate what he perceives as the most serious threat to both national security and regime security: South Korea’s pursuit of absorptive unification. To this end, in late 2023, North Korea abruptly abandoned its long standing doctrine of national reunification, redefined inter Korean relations as relations between “two hostile states,” and began treating South Korea as a foreign country belonging to a different nation.

To implement this new anti-reunification line, the North Korean military throughout 2024 dismantled inter-Korean railways and roads and laid landmines along the border. In October 2024, the General Staff of the Korean People’s Army announced that it would “permanently cut off and seal the border with the Republic of Korea,” which it described as the “primary hostile state and immutable principal enemy,” and would “fortify the border area with hardened defensive structures.” Going forward, North Korea is expected to continue measures aimed at fully separating the two Koreas politically, physically, and under international law.

During the Cold War, South Korea adhered to the principle of the “Koreanization of the Korean Peninsula problem.” This principle weakened considerably after the emergence of the North Korean nuclear issue, as U.S.- North Korea nuclear negotiations came to dominate the agenda. Looking ahead, the United States and Japan may seek to leverage North Korea’s “two state system” narrative to facilitate more flexible engagement with Pyongyang. In particular, both countries have recently reiterated their willingness to engage North Korea in the context of military crisis management and denuclearization. As a result, the likelihood of high-level U.S.-North Korea and Japan North Korea dialogues (including summit meetings) is expected to increase further in 2025.

C. Strengthening of a New Cold War Order on the Korean Peninsula Through North Korea–Russia Military Alliance

The Biden administration, inaugurated in January 2021, and the Yoon Suk Yeol administration, inaugurated in May 2022, showed limited interest in engaging in dialogue with North Korea. While the United States concentrated on countering China and South Korea focused on responding to North Korea’s security threats, and ROK-U.S.-Japan actively advanced trilateral security cooperation. As a result, the trend toward bloc formation in Northeast Asia became more pronounced, with the ROK-U.S.-Japan alignment increasingly set against North Korea, China, and Russia.

It was during this period that the term “new Cold War” began to appear in Kim Jong Un’s speeches. In a September 2021 address to the Supreme People’s Assembly, Kim argued that international politics was shifting toward a “new Cold War” structure as a result of what he described as “unfair bloc formation led by the United States.” At that time, Kim employed the concept of the “new Cold War” primarily as a tool to criticize U.S. behavior. Soon thereafter, however, North Korea came to judge that the emerging “new Cold War” international environment worked to its advantage and began to actively exploit it. Even so, Kim Jong Un did not explicitly label his own foreign policy approach as a “new Cold War strategy.” This restraint was likely influenced by the fact that both China and Russia used the term “new Cold War” chiefly to criticize U.S. style bloc politics rather than to define their own strategic doctrines.

Russia’s invasion of Ukraine in February 2022 became the decisive catalyst for North Korea’s foreign policy to shift fully toward a “new Cold War” orientation. As both Russia and North Korea were subjected to U.S. led sanctions and were engaged in direct or indirect confrontation with the United States, the two countries naturally converged around the formation of an anti-U.S. joint front. North Korea consistently supported Russia’s invasion of Ukraine and provided selected war materiel. In return, Russia supplied North Korea with essential food and fuel by circumventing United Nations Security Council sanctions. This trajectory culminated in March 2024, when Russia exercised its veto against a resolution to extend the mandate of the UN Security Council Panel of Experts on North Korea sanctions, thereby effectively neutralizing the sanctions monitoring mechanism.

In June 2024, Kim Jong Un and Vladimir Putin concluded a military alliance titled the “DPRK-Russia Treaty on Comprehensive Strategic Partnership” at a summit held in Pyongyang. North Korea significantly strengthened alliance cohesion by supplying Russia with large quantities of artillery shells and deploying approximately ten thousand troops, while securing substantial military assistance from Russia in return. It is likely, however, that Kim Jong Un’s primary objective was economic cooperation rather than military support per se. Through troop deployment wages, the supply of ammunition and weapons, and participation in postwar reconstruction, North Korea expanded opportunities for foreign currency earnings. In addition, it appears to have imported large quantities of oil, food, and industrial materials from Russia, items that had previously been restricted due to sanctions. The Eurasian “new Cold War” dynamics triggered by the Russia-Ukraine war thus provided North Korea with a new security and economic escape route.

At the same time, the likelihood that Russia would openly provide North Korea with technological assistance for strategic weapons such as ICBM, advanced missile systems, nuclear powered submarines, or military reconnaissance satellites remains low. As an officially recognized nuclear weapon state under the NPT and one of the few countries possessing ICBM technology, Russia has a vested interest in preserving the existing international nuclear order. It also likely takes into account the possibility of restoring its status as a responsible permanent member of the UN Security Council in the future.

3. Policy Tasks for Lee Jae Myung Administration’s North Korea Policy andStrategies

A. Prioritizing Strengthening Deterrence of the ROK–U.S. Alliance Against North Korean Nuclear Threat

At the December 2023 plenary meeting of the Workers’ Party of Korea, Kim Jong Un designated South Korea as “the most hostile state” and redefined inter-Korean relations as those of “two belligerents at war.” He further directed the “continued expansion of nuclear forces” and preparations for a “great transformation aimed at pacifying the territory of South Korea,” thereby sharply escalating the threat of war against the South. In his policy address to the Supreme People’s Assembly in January 2024, Kim reiterated this position by stating that, in the event of war, the objective of “completely occupying, pacifying, reclaiming, and incorporating the Republic of Korea” should be reflected in the constitution. These statements fueled growing concerns regarding Kim Jong Un’s intent to initiate war and conduct nuclear attacks.

To deter the possibility of such North Korean (nuclear)war provocations, extended deterrence provided by the United States under the ROK–U.S. alliance, including the nuclear umbrella and the Nuclear Consultative Group, currently represents the most realistic and effective policy option. Under the terms of the alliance treaty, the United States is obligated to provide military assistance in accordance with established procedures in the event that South Korea is attacked. In addition, the United States has repeatedly reaffirmed its security commitments to South Korea at the political level. In practice, the two governments have conducted frequent high-level military consultations, combined ROK–U.S. military exercises, and meetings of the Extended Deterrence Strategy and Consultation Group (EDSCG). The United States has also deployed or dispatched various strategic assets to the Korean Peninsula and surrounding regions.

At present, U.S. nuclear policy allows for the possibility of “first-use” of nuclear weapons in wartime when deemed necessary to protect the U.S. homeland and its allies. Nevertheless, doubts regarding the credibility of the U.S. nuclear umbrella have not been fully dispelled. Such skepticism is unlikely to be resolved unless South Korea were to acquire its own nuclear weapons.

The United States also has reasons to provide the nuclear umbrella. If confidence in U.S. extended deterrence were to erode, U.S. allies would face strong incentives to pursue nuclear weapons programs at virtually any cost in order to ensure their survival. Some states might abandon alliance with the United States altogether and instead align themselves with continental Eurasian powers. Such outcomes would run directly counter to US national interests. In practice, the United States has consistently demonstrated a willingness to defend its allies regardless of cost. If the United States was able during the Cold War to protect its allies from the nuclear threats posed by major powers such as the Soviet Union (Russia) and China, there is no compelling reason why it would be unable to protect South Korea from a smaller nuclear-armed state such as North Korea.

In response to the growing North Korean nuclear threat, the United States pledged in the 2023 “Washington Declaration“ to further strengthen its nuclear umbrella and extended deterrence commitments. The United States committed ”to making every effort to consult with South Korea regarding any potential use of nuclear weapons on the Korean Peninsula,“ and ”to ensure that the ROK–U.S. alliance would be more deeply and cooperatively involved in nuclear deterrence related decision making.“ More specifically, the declaration announced ”the establishment of a new ‘Nuclear Consultative Group (NCG)’ aimed at strengthening extended deterrence, discussing nuclear and strategic planning, and managing North Korea’s threats to the nonproliferation regime.“

The creation of the NCG represents a landmark development in the evolution of the ROK–U.S. alliance. In the past, South Korea and the United States maintained close diplomatic coordination focused on the denuclearization of North Korea, but there was little meaningful consultation at the military level regarding the potential use of U.S. nuclear weapons. During the Cold War, numerous U.S. tactical nuclear weapons were stationed at U.S. bases in South Korea, yet South Korea had limited knowledge of their numbers, locations, or operational employment. While the United States occasionally demonstrated strategic capabilities in response to North Korean provocations, such actions were discretionary and unilateral. Against this historical backdrop, the establishment of the NCG constitutes a significant departure from traditional U.S. nuclear policy and provides a more visible and institutionalized guarantee of the U.S. nuclear umbrella for South Korea.

B. Promoting “Peaceful Coexistence“ Based on a Provisional Two-State Framework to Stabilize Inter-Korean Relations and Prevent War

The two Koreas have been locked in what can best be described as a “unification competition,” the most intense security competition since the division of the Korean Peninsula. A significant shift occurred in September 1991 with the simultaneous admission of South Korea and North Korea to the United Nations. This marked the first emergence of an international legal order on the Peninsula in which the Republic of Korea and the Democratic People’s Republic of Korea coexisted as two distinct states. As of 2024, South Korea maintains diplomatic relations with 192 countries, while North Korea has diplomatic ties with 159 countries. A total of 156 countries maintain relations with both Koreas simultaneously. From the perspective of international law, these 156 states effectively recognize South and North Korea as separate and independent sovereign entities.

In December 1991, the two Koreas signed the Inter-Korean Basic Agreement, in which they committed to mutual recognition and respect of each other’s systems, non interference in internal affairs, non use of force and non aggression, cessation of slander, and an end to attempts at subversion or destruction. Through this agreement, the two sides effectively accepted a “de facto two state” framework. However, at North Korea’s insistence, inter-Korean relations were defined not as “relations between states but as a special relationship temporarily formed in the process of pursuing unification.” As a result, both Koreas remained trapped in a zero sum framework of unification competition in which each side sought the eventual absorption of the other.

This paper argues that preventing war and establishing durable peace on the Korean Peninsula requires acceptance of a provisional two state framework until conditions for peaceful unification are restored. Under this approach, the goal of unification is reaffirmed, but peaceful coexistence is prioritized as an interim objective. Specifically, the paper proposes the conclusion of a new Inter-Korean Basic Treaty that legally institutionalizes peaceful coexistence under a two-state framework until a genuine environment for peaceful unification emerges.

This Basic Treaty would inherit the core principles of the Basic Agreement (1991) while elevating them into a formal treaty structure. To ensure its international legal status and enforceability, the treaty would be signed by the leaders of both Koreas, ratified by their respective legislatures, and registered as an international treaty with the United Nations Secretariat in accordance with Article 102 of the UN Charter.

Former Prime Minister Lee Hong-koo, who served as Minister of Unification in the early post Cold War period, later reflected on the trajectory of the two state approach in inter Korean relations (Hong-koo Lee, “Systemizing the division,” JoongAng Daily, September 14, 2015). “The formula stated that the two government systems of South and North Korea will coexist and cooperate in the peninsula for a significant period of time. In accordance with this "two states solution," the two Koreas signed a Basic Agreement in 1991, joined the United Nations at the same time and issued the joint declaration of denuclearization of the Korean Peninsula.” From this perspective, completing this unfinished institutional project requires South Korea to revisit and advance the two state framework once again.

C. Advancing “Phased Denuclearization” Beginning with a “Nuclear Freeze” through the Resumption of North Korea Nuclear Diplomacy

Over the past several years, a majority of North Korea nuclear experts in the United States, along with former chief negotiators on North Korea’s nuclear issue, have emphasized both the risks associated with the continued expansion of North Korea’s nuclear capabilities and the limited feasibility of achieving complete denuclearization. Against this assessment, they have increasingly proposed alternatives that begin with a nuclear freeze and move toward phased denuclearization or negotiations on nuclear arms control. Against this backdrop within the United States, there is a high likelihood that a second Trump administration would pursue negotiations focused on phased denuclearization or nuclear arms control. At the same time, the resumption of U.S. North Korea dialogue is expected to generate substantial domestic controversy, particularly regarding Trump style unilateral diplomacy, the possibility of Korea being sidelined, and the pursuit of nuclear arms control. Thorough preparation will therefore be required.

For example, in December 2023, Politico reported, citing individuals associated with Trump’s campaign, that Trump was considering an approach under which the United States would ease economic sanctions and provide assistance if North Korea agreed to freeze its nuclear activities and halt the development of new weapons. Although Trump, then a presidential candidate, publicly dismissed the report as fake news, questions surrounding a potential exchange involving a nuclear freeze and sanctions relief have persisted.

In addition, Trump nominated Alex Wong, who served as deputy special representative for North Korea under Special Representative Stephen Biegun during the first Trump administration, to the position of principal deputy national security advisor at the White House. In announcing the nomination, President elect Trump explicitly highlighted Wong’s experience in U.S.-North Korea summit. Taken together, it suggests that a second Trump administration is likely to pursue renewed U.S.-North Korea summit and may favor phased denuclearization as its preferred approach to addressing the North Korean nuclear issue.

As a concrete response strategy toward the Trump administration’s policy on North Korea’s nuclear issue, the first suggestion is that President Trump send a personal letter to Chairman Kim Jong Un at his earliest convenience. A letter from Trump would carry significant symbolic weight for Kim Jong Un and would be difficult for him to disregard entirely. The letter should reaffirm the continued validity of the “Singapore Joint Statement” (2018) adopted by the two leaders. Should Kim respond positively, such an exchange would effectively reconfirm, at the leadership level, the three core objectives contained in the joint statement: the complete denuclearization of the Korean Peninsula, the normalization of U.S.–North Korea relations, and the establishment of a peace regime.

Second, there is no need to react excessively to references by U.S. officials to “nuclear arms reduction negotiations.” In principle, nuclear arms reduction refers to negotiations between recognized nuclear weapon states under the “Nuclear Non Proliferation Treaty (Article VI),” in which both sides reduce their nuclear arsenals. North Korea, however, is not a recognized nuclear weapon state and therefore cannot be a party to nuclear arms reduction negotiations under international law. At the same time, phased denuclearization is realistically unavoidable. In fact, previous U.S.–North Korea agreements, including the U.S.-North Korea Geneva Agreed Framework (1994) and the Six-Party Talks (2003), also pursued phased denuclearization beginning with a nuclear freeze. Just as past negotiations with North Korea were not described as nuclear arms reduction talks, there is no reason to characterize future U.S.–North Korea nuclear negotiations in such terms.

Third, the ROK and U.S. governments should convene working level consultations at an early stage to jointly develop a denuclearization roadmap. During the first Trump administration, a “conceptual denuclearization roadmap” was previously formulated. Drawing on this experience, raising and discussing Korea’s concerns in advance would help prevent potential disputes or misunderstandings, including those related to “Korea passing” or “the framing of nuclear arms reduction negotiations.” In order to effectively advance Korea’s position in ROK U.S. negotiations, (and to avoid repeating past precedents such as the end of war declaration or the unification doctrine) it is first necessary to develop a Korea specific denuclearization and peace roadmap. This roadmap should be formulated by experts spanning conservative, progressive, and centrist perspectives, and should reflect both a Korean roadmap for denuclearization reflecting “the geopolitical realities of the Korean Peninsula and a broader vision of denuclearization, peace, and prosperity.”

D. Promoting Inter-Korean and U.S.–North Korea Politico-Military Talks to Reduce “Nuclear Risks” and Prevent Military Escalation

North Korea has traditionally perceived itself as militarily weaker than the ROK–U.S. alliance and has therefore adopted a war strategy that emphasizes preemptive and surprise attacks aimed at achieving war objectives before the large scale reinforcement of U.S. forces. During its nuclear development process, North Korea also feared that its nuclear capabilities could be neutralized by a U.S. first strike. As a result, it pursued an “asymmetric escalation nuclear strategy” under which it would respond to any enemy attack by escalating with nuclear weapons.

This tradition of offensive military strategy has extended into the nuclear domain. In the Law on Policy on Nuclear Forces adopted in 2022, North Korea explicitly threatens preemptive, automatic, and discretionary nuclear strikes against South Korea and the United States. Among the nuclear strategies of the nine existing nuclear-armed states, this posture is widely assessed as unprecedented in its level of offensiveness.

The ROK military has likewise adopted the principle of “strategic strikes,” commonly referred to as the “Kill Chain,” in order to prevent North Korea’s potential surprise and preemptive use of nuclear weapons. This concept is designed to detect indications of an impending launch of North Korean nuclear missiles and to neutralize them through preemptive strikes prior to launch. However, under conditions in which North Korea’s doctrine of asymmetric escalation and preemptive nuclear use confronts Korea’s strategy of preemptively neutralizing North Korean nuclear missile capabilities, even a minor inter Korean military incident carries a high risk of becoming a trigger for nuclear use.

As discussed earlier, planned North Korean nuclear attacks against South Korea and the United States are to be deterred through the U.S. nuclear umbrella and extended deterrence. At the same time, North Korea’s high level of nuclear readiness and its offensive nuclear doctrine increase the likelihood that accidents, misperceptions, or miscalculations could lead to unintended nuclear use, or that a limited military clash could escalate into nuclear employment. Reducing these “risks of nuclear use” therefore requires specific and targeted measures.

Specifically, political and military talks should be proposed and actively pursued between South Korea-North Korea, U.S.-North Korea, or ROK-U.S.-North Korea. Through measures such as reducing military tensions, maintaining communication during crises, strengthening crisis management, and exchanging military information, efforts should be made to reduce the risks associated with nuclear use. In recent years, the international community has increasingly emphasized the reduction of nuclear use risks as a key task in arms control and nonproliferation, as the revival of great power politics and geopolitical competition has heightened the possibility of nuclear use. Measures proposed toward this end include enhancing transparency regarding nuclear capabilities, easing nuclear use postures, reducing the role of nuclear weapons in security policy, implementing a moratorium on nuclear testing, prohibiting the production of fissile material for military purposes, and creating conditions conducive to nuclear arms reduction and denuclearization. These issues should be addressed in political and military talks with North Korea in order to reduce the risks of escalation and nuclear use.