The Lee Jae Myung administration is investing considerable effort in acquiring conventionally armed nuclear-powered submarines (hereafter, SSNs) as part of its drive to build a technologically advanced military, and in securing uranium enrichment and spent nuclear fuel reprocessing capabilities on grounds of energy security. The government regards all three as security matters requiring U.S. cooperation and alliance-level agreement. In an interview with a media outlet on May 28, Minister of Foreign Affairs Cho Hyun outlined the administration's plan: to "revise the nuclear cooperation agreement [with the United States] as quickly as possible so that we can conduct enrichment and reprocessing, and to accelerate progress on nuclear-powered submarines as well."¹⁾

However, there is a fundamental flaw in viewing SSNs, enrichment, and reprocessing solely as bilateral issues with the United States. It is often forgotten that a document that has comprehensively governed South Korea's nuclear-related policies and positions since 1991 remains in effect. From President Roh Tae-woo to President Lee Jae Myung, successive South Korean governments, regardless of their political orientation, have pursued a denuclearization policy renouncing nuclear armament and a policy of peaceful use of nuclear energy. The foundation of both policies is the Joint Declaration on the Denuclearization of the Korean Peninsula (hereinafter, the Joint Declaration), agreed upon by the two Koreas on December 31, 1991. The current administration's END Initiative, a policy framework aimed at ending the Cold War and achieving peaceful coexistence through exchange, normalization of relations, and denuclearization, is likewise a continuation of North Korea policy grounded in the Joint Declaration on the Denuclearization.

Although the Joint Declaration is not legally binding, it has been politically binding and has served as the foundation of South Korea's denuclearization policy, as no administration has ever declared that it has lost its effect. However, because the Joint Declaration contains provisions prohibiting SSNs, uranium enrichment, and reprocessing (hereinafter, E&R), a contradiction has emerged as the government simultaneously pursues policies that uphold the Joint Declaration (denuclearization) and policies that violate it (SSNs and E&R). Now the Joint Declaration itself has begun to constrain the pursuit of policy in an era of SSNs, E&R. This paper argues that denuclearization is incompatible with SSNs, uranium enrichment, and reprocessing, and that, before engaging in consultations with the United States, the South Korean government should free itself from the political fetters of the Joint Declaration. It proposes the following measures: (1) confirming the loss of effect of the Joint Declaration; (2) shifting North Korea policy toward "gradual dismantlement of North Korea's nuclear weapons program"; (3) temporarily redeploying U.S. tactical nuclear weapons to the Korean Peninsula and pursuing trilateral—the two Koreas and the U.S.—nuclear arms reduction talks until the dismantlement of North Korea's nuclear weapons program is completed; and (4) changing the terminology from "nuclear-powered submarine" to "atomic-powered submarine."

| The Clash Between Denuclearization and Nuclear-Powered Submarines, Uranium Enrichment, and Reprocessing

"Denuclearization" first appeared in President Roh Tae-woo's Declaration on the Denuclearization and Establishment of Peace on the Korean Peninsula, issued on November 8, 1991 (hereinafter, the Declaration). This declaration, which represented the South Korean government's first official position on the nuclear issue since the signing of the Armistice Agreement and served as the basis for the Joint Declaration, consisted of five provisions:

1. The peaceful use of nuclear energy

2. The five principles of denuclearization—prohibiting the manufacture, possession, storage, deployment, and use of nuclear weapons

3. Faithful compliance with the NPT and the IAEA Safeguards Agreement

4. Prohibition of reprocessing and uranium enrichment facilities

5. Participation in international efforts to eliminate other weapons of mass destruction

President Roh Tae-woo issued the declaration out of the belief that "we had to take the initiative first to prevent North Korea from developing nuclear weapons."²⁾ On December 18, 1991, he further declared that there were "no nuclear weapons, not a single one, anywhere in our country at this moment," thereby declaring the absence of nuclear weapons on the Korean Peninsula. He argued that, since the Declaration announced on November 8 had been fully implemented, North Korea had lost any justification for developing nuclear weapons or refusing inspections. He therefore urged North Korea to promptly accept IAEA inspections and abandon its reprocessing and uranium enrichment programs. President Roh's declaration of the absence of nuclear weapons also indirectly confirmed that the U.S. tactical nuclear weapons stationed in South Korea had been completely withdrawn.³⁾

Following a series of negotiations, South and North Korea reached agreement on the Joint Declaration on the Denuclearization of the Korean Peninsula at Panmunjom on December 31, 1991. The two sides formally signed the Joint Declaration on January 20 of the following year, and it entered into force on February 19. The Joint Declaration consists of a preamble and six provisions:

Preamble: South and North Korea declare as follows in order to eliminate the danger of nuclear war by denuclearizing the Korean Peninsula, create favorable conditions and an environment for peace and peaceful reunification in our country, and contribute to peace and security in Asia and around the world.

1. South and North Korea shall not test, manufacture, produce, receive, possess, store, deploy, or use nuclear weapons.
2. South and North Korea shall use nuclear energy solely for peaceful purposes.
3. South and North Korea shall not possess nuclear reprocessing facilities or uranium enrichment facilities.
4. In order to verify the denuclearization of the Korean Peninsula, South and North Korea shall conduct inspections of facilities designated by either side and agreed upon by both sides, in accordance with the procedures and methods prescribed by the South-North Joint Nuclear Control Commission.
5. South and North Korea shall establish and operate the South-North Joint Nuclear Control Commission within one month of the entry into force of this Joint Declaration for the purpose of implementation.
6. This Joint Declaration shall enter into force on the day on which South and North Korea exchange its text after completing the respective procedures required for its entry into force.

Provision 1 sets out the meaning of denuclearization through the "eight principles of denuclearization" and is, in effect, a stringent provision that blocks virtually every avenue toward acquiring nuclear weapons. Successive South Korean governments have adhered to these eight principles of denuclearization, whereas North Korea violated the provision from the outset and ultimately succeeded in developing nuclear weapons. North Korea's decision to abruptly agree to the Joint Declaration in 1991, which incorporated most of the positions advanced by the Roh Tae-woo administration, was a tactical move intended to avert the threat to the regime posed by the collapse of the Cold War system. While publicly professing its commitment to denuclearization, North Korea continued to develop its nuclear capabilities behind the curtain, deceiving the international community, and repeatedly cycling between negotiations and confrontation.

Provisions 2 and 3 either conflict with or explicitly prohibit activities involving SSNs and E&R. The provision stipulating that nuclear energy shall be used solely for peaceful purposes conflicts with SSN programs, which require the military use of nuclear energy. As demonstrated by the cases of the AUKUS program, the military use of nuclear energy is distinct from the development of nuclear weapons and is permitted under the NPT. Thirty-five years after its adoption, the Joint Declaration has thus become a significant obstacle to South Korea's efforts to strengthen its defense capabilities. The provision prohibiting the possession of E&R facilities is inconsistent with the NPT regulations. As demonstrated by NPT member states such as Japan, the Netherlands, and Germany, which possess such facilities, Provision 3 also raises the issue that South Korea has voluntarily relinquished rights that are otherwise permitted under the NPT.

Because the eight principles of denuclearization set forth in Provision 1, the principle of peaceful use in Provision 2, and the prohibition on E&R in Provision 3 could effectively block all pathways for a non-nuclear-weapon state to acquire nuclear weapons, successive U.S. administrations placed considerable importance on implementing the Joint Declaration. The Obama administration even regarded the Joint Declaration as a model agreement that could serve as a standard for application to other countries, underscoring the extent to which the document aligned with U.S. interests. However, the U.S. strategy of killing two birds with one stone—using denuclearization to prevent both South and North Korea from developing nuclear capabilities—ultimately achieved less than half of its intended objective: it failed to prevent nuclear development by its adversary, North Korea, while succeeding only in constraining nuclear development by its ally, South Korea.

| The Inherent Flaws of the (Joint) Declaration on Denuclearization

The Denuclearization Declaration announced by President Roh Tae-woo in 1991 and the Joint Declaration on the Denuclearization agreed upon by South and North Korea revealed numerous problems, not only in their substance but also in their formulation and implementation.⁴⁾

First, the Denuclearization issued by President Roh Tae-woo, which served as the basis for the Joint Declaration, did not adequately reflect the views of South Korea's atomic energy community during its drafting and review. At the time, questions were raised as to whether it was a top-down decision made hastily for political considerations. In particular, the exclusion of the government ministries and expert groups that would have been most directly affected by the policy raised a serious concern. The decision at the time to voluntarily relinquish South Korea's rights permitted under the NPT in the name of preventing North Korea's nuclear development deserves careful reexamination, even if long overdue.

Second, the policy lacked long-term considerations not only from the perspective of energy security extending beyond reunification, but also from scientific and technological as well as military and strategic perspectives. By hastily imposing political constraints on nuclear research, development, and utilization in a resource-poor country, the decision caused substantial losses to the national interests across a range of interconnected areas, including the economy, science, and technology.

Third, despite being a matter of national importance with potentially far-reaching implications not only for national security but also for the lives of the Korean people, the policy was adopted without sufficient prior consultation with the National Assembly, public hearings or expert consultations. Had the government at the time appropriately utilized the National Assembly and civil society organizations to guard against making unilateral concessions, it could have secured a stronger position in its relations with the United States and North Korea.

Fourth, the media neglected to adequately point out the problems inherent in the two declarations. Rather than reflecting the views of the scientific and technological community, highlighting the problems in the declarations, and encouraging policy revisions, the media at the time largely accepted the government's policy without sufficient scrutiny, failing to gather a range of views and provide objective and accurate information that would enable the public to form a balanced perspective.

Fifth, politicians and senior officials involved in the denuclearization negotiations focused more on concluding the agreement itself than on the substance of the agreement and its implementation, displaying a tendency to emphasize publicity and promote the outcome as a success. It is true that, in early 1992, many South Koreans believed that the North Korean nuclear issue was essentially resolved. By presenting and promoting the positive aspects of the agreement to the public, the officials contributed to forming an illusion that "reaching an agreement itself meant that the problem had been solved." In the meantime, North Korea did not abandon its nuclear ambitions and continued to advance its nuclear program step by step. After more than three decades of this pattern being repeated, South Korea ends up being under harsh threat by nuclear-armed North Korea.

Sixth, from the time the Joint Declaration was concluded, the failure to strictly enforce the agreement while effectively tolerating and overlooking North Korea's clear violations sent the wrong signal to Pyongyang. The international community began strengthening sanctions against North Korea following its first nuclear test on October 9, 2006. Prior to that, efforts largely remained at the level of managing North Korea's nuclear development, with South Korea and the United States primarily alternating between negotiations and sanctions. For example, the reprocessing facility currently located at Yongbyon in North Korea already existed at the time the Joint Declaration was concluded, under the name "Radiochemical Laboratory." During his visit to Yongbyon in May 1992, IAEA Director General Hans Blix confirmed that the facility was a "plant-scale reprocessing facility in violation of the Joint Declaration." By allowing North Korea's blatant violation of the Joint Declaration to go unchecked, it had, in effect, become a dead letter from the beginning.

Seventh, the verification provisions for implementing the agreement (Provision 4) failed to meet even the minimum standards of effective arms control, ultimately setting the agreement on a path toward dysfunction. Verification provisions, as an integral part of an overall agreement, should be negotiated and implemented as a package alongside the matters subject to regulation. The Joint Declaration, however, followed a different sequence: the two sides first agreed on the matters to be regulated and then established the Joint Nuclear Control Commission to negotiate verification procedures at a later stage. This overlooked the fact that an agreement on regulated matters is meaningless unless verification is secured. It was also technically problematic to stipulate that the sites subject to inspection would be those selected by the other side but agreed upon by both parties. This effectively created only a partial verification arrangement, since inspections could not be conducted without the other side's consent. Ultimately, the Joint Declaration failed to be properly implemented and broke down as disagreements emerged over verification.

Eighth, over the 35 years since the conclusion of the Joint Declaration, successive governments and political circles, as well as current and former senior government officials, academics, members of the media, and other opinion leaders in South Korea have failed to make serious efforts to bring the reality of the failure of denuclearization diplomacy into the public debate and promote a policy shift. Only a handful of figures, including Lee Hong-koo, former Deputy Prime Minister for Unification; former President Kim Young-sam; Cho Myoung-gyon, former Minister of Unification; Kim Jin-hyun, former Minister of Science and Technology; and Chung Dong-young, current Minister of Unification, have raised concerns about the shortcomings of denuclearization and the need to change nuclear policy.

In 1994, Lee Hong-koo, then Deputy Prime Minister for Unification, was the first to publicly raise the possibility of shifting the policy. He stated that if North Korea's possession of nuclear weapons were confirmed by the international community, the Joint Declaration would become null and void, and that if North Korea continued to maintain the Radiochemical Laboratory, the Joint Declaration should be reconsidered from a new perspective.⁵⁾

In a luncheon meeting with U.S. Ambassador to South Korea Alexander Vershbow in April 2008, former President Kim Young-sam expressed regret over having blocked the Clinton administration's plan to strike North Korea's nuclear facilities at Yongbyon in 1994. According to a cable that Ambassador Vershbow sent to Washington on April 25, 2008, and that WikiLeaks released on April 30, 2011, Kim said that former President Bill Clinton and then Secretary of Defense William Perry had wanted to attack North Korea in 1994 and would have done so had he not intervened. Looking back, Kim reportedly said that "we would all have been better off if he had allowed the United States to strike the Yongbyon nuclear facility."⁶⁾

On January 9, 2019, at a meeting of the National Assembly's Special Committee on Inter-Korean Economic Cooperation, Minister of Unification Cho Myoung-gyon publicly acknowledged for the first time that North Korea's definition of denuclearization differed from that of South Korea.⁷⁾ At the government level, this was the first official acknowledgment that North Korea was using the guise of denuclearization to deceive the international community.

In a media interview two years ago, Kim Jin-hyun, former Minister of Science and Technology, sharply criticized the North Korea policies by successive South Korean governments. He made the following argument:⁸⁾

The more than thirty individuals who served as presidents, directors of the National Intelligence Service, and ministers of foreign affairs and national defense since the 1980s should issue a joint apology and statement of contrition for their responsibility for the failure to properly address North Korea policy and the North Korean nuclear issue. At the time, as the entire world entered a period of détente, North Korea's international standing rapidly declined. By the 1990s, the Soviet Union had collapsed, North Korea was experiencing widespread starvation, and even China, in addition to the Soviet Union, was reaching out to South Korea for assistance. I believe that, had our government acted properly at the time, inter-Korean reunification could have been achieved. In the United States, there were acknowledgments and apologies for failures in North Korea policy, yet is it really the case that not a single person in South Korea, the country directly involved, has offered an apology?

Minister of Unification Chung Dong-young also recently stated at the "2026 International Forum on the Korean Peninsula" that North Korea's nuclear capabilities had increased 100,000-fold over 34 years, from the 90 grams of plutonium it reported to the IAEA in 1992 to the 57 nuclear weapons cited by President Trump. He said, "It is clear that an approach centered on 'complete denuclearization' is no longer sustainable."⁹⁾ This effectively amounted to an acknowledgment that the denuclearization policies pursued by successive South Korean governments on the basis of the Joint Declaration is on their last legs.

| Policy Recommendations

1. Government-Level Confirmation of the Loss of Effect of the Joint Declaration

The Joint Declaration is a document that has revealed numerous problems throughout the entire process of its formulation, negotiation, and implementation. The fact that North Korea has continued to maintain the prohibited reprocessing facility under the guise of the "Radiochemical Laboratory" and is still using it for its nuclear program vividly illustrates the stark reality of the Joint Declaration. From the outset, North Korea, with the goal of undermining the ROK-U.S. alliance, rebranded the "nuclear-weapon-free zone," a concept left by Kim Il Sung as a legacy instruction, as "denuclearization," thereby deceiving South Korea and the United States while pursuing its nuclear program.¹⁰⁾ Immediately following its second nuclear test in May 2009, North Korea categorically rejected the implementation of the Joint Declaration while opposing UN Security Council sanctions. It would be difficult for the South Korean public to accept a policy of continuing to uphold a document that the other party violated almost as soon as the ink had dried and then ceased even to acknowledge after completing its nuclear weapons development.

Even in light of the international environment surrounding the Korean Peninsula, the era of denuclearization diplomacy has passed. It has been a long time since China and Russia ceased supporting sanctions against North Korea, and following the North Korea-Russia military alliance treaty, calls for North Korean denuclearization have effectively disappeared.¹¹⁾ Denuclearization was absent from the agendas of the China-Russia summit in May and the North Korea-China summit in June. Reports that President Xi Jinping offered Kim Jong Un normal trade relations on the condition that North Korea pursue the development of weapons of mass destruction, including nuclear weapons, with China's consent also illustrate the rapidly changing security environment in Northeast Asia.¹²⁾ It has also been more than a decade since a broad consensus emerged in the United States that denuclearization diplomacy had failed.¹³⁾ With a North Korea-U.S. summit in mind for this fall, President Trump unilaterally scaled back ROK-U.S. combined military exercises. When asked whether the denuclearization of North Korea remained the goal, he said that he did not want to discuss it.¹⁴⁾ He also publicly stated that North Korea already possesses 57 powerful nuclear weapons and that this should never have been allowed to happen.¹⁵⁾ These remarks can be read as indicating that the United States, too, regards complete denuclearization as increasingly difficult to achieve.

Yet both the government and the media in South Korea continue to react with alarm to news reports that appear to acknowledge North Korea's possession of nuclear weapons. When President Trump, shortly after taking office in 2025, expressed optimism about U.S.-North Korea dialogue in the Oval Office and referred to North Korea as a "nuclear power," South Korean media responded with headlines such as "'U.S. Mainstream View Reflects the Impossibility of Denuclearization,'" "'Trump Calls North Korea a 'Nuclear Power,' Upending the International Order from Day One,'" "'Trump Calls North Korea a 'Nuclear Power'... Undermining Denuclearization from Day One,'" and "''Trump Recognizes North Korea's Nuclear Weapons'... Seismic Shift on the Korean Peninsula, Reset Begins for the World," revealing their sense of consternation.¹⁶⁾ These reactions illustrate how the media remain constrained by the stereotype that North Korea, like South Korea, will eventually give up its nuclear weapons entirely. The South Korean government and media are still debating over the use of the phrase "resolution of the North Korean nuclear issue" instead of the term "denuclearization," in the readout of the August 24 phone call between the ROK and U.S. Ministers of Foreign Affairs.¹⁷⁾

The vast majority of South Koreans also do not believe that North Korea will denuclearize. Various opinion polls indicate that roughly nine out of ten South Koreans do not expect North Korea to denuclearize. For example, according to the Korea Institute for National Unification's 2022 public opinion survey, 91.6 percent of respondents believed that denuclearization was impossible. Only 22 percent of respondents said that denuclearization should remain the policy response to the growing North Korean nuclear threat, according to a Segye Ilbo survey conducted in February 2025. It has reached the point where criticism may reasonably be raised that maintaining a commitment to denuclearization that the public itself does not believe in is no longer tenable.

In light of the systemic deficiencies surrounding the Joint Declaration, the reality of North Korea's advancing nuclear capabilities, changes in the international environment, and public opinion, the South Korean government should officially declare that "the Joint Declaration on the Denuclearization has lost its effect due to North Korea's persistent violations." The purpose of such a declaration would be to free the government from the political constraints imposed by the Joint Declaration and broaden the scope of available policy options. This would be a bold declaration grounded in sincerity and a sense of responsibility, demonstrating a commitment to charting a new course based on the lessons of past failures. If the government makes such a declaration, the National Assembly should welcome the government's decision by lending bipartisan support through a resolution.

2. Shifting North Korea Policy from "Denuclearization" to "Gradual Dismantlement of North Korea's Nuclear Weapons Program"

The government should adopt "gradual dismantlement of North Korea's nuclear weapons program" (hereafter, gradual dismantlement) as its new North Korea policy while simultaneously declaring that the Joint Declaration has lost its effect. It would be desirable for the government to use gradual dismantlement in all official and unofficial statements and documents, both domestically and internationally, as well as in public discourse. A policy of gradual dismantlement would free South Korea from the constraints of a denuclearization policy that has pursued the illusory goal of North Korea abandoning its nuclear weapons, recognize North Korea's nuclear arsenal as a threat to the survival of the South Korean state, and open the way for a more pragmatic and proactive response than in the past.

Some may criticize abandoning the denuclearization policy as tantamount to accepting North Korea's nuclear weapons. However, whether North Korea's nuclear weapons are accepted is not an appropriate criterion for evaluating the policy. Regardless of South Korea's position that North Korea's nuclear weapons cannot be accepted, North Korea already possesses nuclear weapons. Using acceptance or non-acceptance of North Korea's nuclear weapons as the criterion would merely reaffirm the failure of the denuclearization policies pursued by successive South Korean governments. Moreover, abandoning the denuclearization policy does not mean abandoning the longstanding goal of a "Korean Peninsula free of nuclear weapons." Rather, the fundamental aim is to achieve this ultimate goal through a new policy of gradual dismantlement, taking into account the inherent problems of the Joint Declaration and the transformed security environment over the 35 years since its conclusion.

Because reducing the scale of North Korea's nuclear weapons program to a certain level is essential before its complete dismantlement, a policy of gradual dismantlement could substantiate and complement President Lee Jae Myung's proposal to prioritize a nuclear freeze. Since reducing North Korea's nuclear capabilities is a process that would take considerable time, it would be reasonable to manage inter-Korean relations on the basis of a freeze at the current level, then proceed gradually through successive stages of reduction over time, and ultimately reach the goal of complete dismantlement of North Korea's nuclear weapons program. This is neither a reckless notion of achieving nuclear dismantlement all at once nor an irresponsible policy of indefinitely postponing it. As a pragmatic alternative that takes into account the reality of North Korea, which regards nuclear weapons as essential to its survival, as well as the historical experience of nuclear arms reduction, it could win broad public support.

To facilitate the government's priority initiatives involving SSNs and E&R, it would also be appropriate to address the Joint Declaration, which has become an obstacle to their implementation. Given that the United States is well aware of the conflict between the Joint Declaration and these initiatives, it may seek a clear position from South Korea regarding the Joint Declaration. The controversy in the United States over the recently concluded U.S.-Saudi nuclear cooperation agreement, which includes a provision allowing Saudi Arabia to establish enrichment facilities subject to a two-year prior review, should also be taken into consideration. On the premise that the United States may be the first to raise the issue of the Joint Declaration once substantive bilateral discussions begin, it is necessary to preemptively eliminate any grounds that could give the other side cause to do so.

3. Temporary Redeployment of U.S. Tactical Nuclear Weapons and Trilateral Nuclear Arms Reduction Negotiations among South Korea, North Korea, and the United States

A policy of gradual dismantlement is grounded in the sobering reality that South Korea will have to live under the shadow of North Korea's nuclear weapons for a considerable period of time, and that the Korean Peninsula has entered the nuclear age. Since President Roh Tae-woo's declaration in December 1991 that there would be no nuclear weapons on the Korean Peninsula, South Korea has relied on extended deterrence provided by the United States "Nuclear Triad." As North Korea's nuclear development became increasingly overt, South Korea's reliance on the Nuclear Triad grew steadily and reached its peak under the Yoon Suk Yeol administration. However, because the Nuclear Triad consists of forces designed primarily to defend the U.S. mainland and to deter nuclear confrontation among big nuclear powers, its use to deter North Korea's nuclear threat on the Korean Peninsula entails significant drawbacks. A careful examination of these problems at both the strategic and operational levels leads to the conclusion that the Nuclear Triad should not be used on the Korean Peninsula, or, in other words, that it cannot provide credible nuclear deterrence against North Korea.¹⁸⁾

To address North Korea's nuclear threat against South Korea, tailored nuclear deterrence capabilities specifically suited to the Korean Peninsula theater are needed. An alternative that could deter North Korea from using tactical nuclear weapons against South Korea while minimizing the possibility of opposition from China and Russia would be to redeploy U.S. tactical nuclear warheads withdrawn from the Korean Peninsula in 1991. Because their destructive power is substantially lower than that of strategic nuclear weapons, making them more likely to be used in a contingency, they would provide more credible deterrence against North Korea. Only by achieving "nuclear parity" between South and North Korea through the redeployment of tactical nuclear weapons can South Korea's security be assured in the nuclear age on the Korean Peninsula.

Alongside the redeployment of tactical nuclear weapons, South Korea and the United States could propose nuclear arms reduction negotiations with North Korea. If a U.S.-North Korea summit is held in the future, the nuclear issue will clearly be on the agenda, and the focus is expected to be on limiting North Korea's intermediate- and long-range nuclear forces that directly threaten the United States. Even if only North Korea's intercontinental ballistic missiles capable of threatening the U.S. mainland were regulated, President Trump could declare victory by claiming that the North Korean threat had been eliminated. The problem, however, lies with North Korea's short-range missiles and multiple rocket launchers capable of reaching the Korean Peninsula only. To counter these North Korean tactical nuclear capabilities, South Korea would likewise need to possess a certain level of tactical nuclear capability. The primary purpose would be to deter the North Korean nuclear threat, while the secondary purpose would be to use such capabilities as leverage in nuclear arms reduction negotiations and as a means of achieving phased reductions in North Korea's nuclear arsenal. In conclusion, the redeployment of tactical nuclear weapons is a practical and useful option that could be implemented immediately, and a policy alternative that could garner bipartisan agreement in South Korea as well as U.S. consent.¹⁹⁾

The stipulation that the redeployment of tactical nuclear weapons would be "temporary" means that these weapons could be reduced proportionally in line with the level of North Korea's nuclear dismantlement. The core rationale of the proposed trilateral nuclear arms reduction talks among South Korea, North Korea, and the United States is to use tactical nuclear weapons as a bargaining instrument in negotiations and ultimately achieve both the complete dismantlement of North Korea's nuclear weapons and the complete withdrawal of the redeployed U.S. tactical nuclear weapons, thereby realizing the ultimate goal of a Korean Peninsula free of nuclear weapons.

On August 28, National Security Adviser Wi Sung-lac stated that, should U.S.-North Korea dialogue resume, the government would work to ensure that South Korea is not sidelined.²⁰⁾ Under the current circumstances, however, exclusion remains a real possibility. In the nuclear world, nuclear issues are discussed only among nuclear-armed states, and non-nuclear states are left out. North Korea, well aware of this dynamic, has treated South Korea as a second-tier state ever since completing its own nuclear weapons program. In a lengthy statement on major international issues issued on August 19, for example, Kim Yo Jong, Director of the General Affairs Department of the Workers' Party of Korea, addressed the United States, Russia, and Japan at length, criticizing Washington, underscoring the military alliance with Moscow, and expressing wariness over Tokyo's military expansion, while dismissing Seoul with only a brief mention of ROK-U.S. combined military exercises and offering no response to the South Korean government's calls for dialogue, including President Lee Jae Myung's August 15 Liberation Day address. It is also worth remembering that it was the Trump administration that signed an MOU with Iran directly undermining the interests of Israel, a close U.S. ally that had fought alongside Washington in two wars since 2025.²¹⁾ Without nuclear assets on South Korean soil, South Korea will not have a seat at the table in nuclear-related discussions—that is the reality of the nuclear age.

Minister of Unification Chung Dong-young has argued that complete denuclearization is unrealistic and described President Lee Jae Myung's proposal for a "pacemaker" role as "moving proactively and actively to create space and bring about U.S.-North Korea dialogue."²²⁾ The four-party talks among South Korea, North Korea, the United States, and China that he proposed as an alternative, as well as six-party talks with the participation of Japan and Russia, could also be pursued in parallel with, and separately from, South-North-U.S. nuclear arms reduction negotiations as part of broader efforts to promote peace in Northeast Asia. The fundamental premise of any shift away from the denuclearization policy, however, must be that South Korea secures nuclear deterrence capabilities sufficient to respond to the actual nuclear threat posed by North Korea. Otherwise, regardless of the government's intentions, such a policy shift could have significant political repercussions by inviting criticism that it amounts to accepting North Korea's nuclear weapons and surrendering to a nuclear-armed North Korea.

4. Replacing the Term "Nuclear-Powered Submarine" with "Atomic-Powered Submarine"

It is advisable to replace the term "nuclear-powered submarine" with the more modest designation "atomic-powered submarine." While "nuclear-powered submarine" emphasizes the strategic significance of nuclear propulsion and may offer the South Korean public some reassurance in the context of countering North Korea's nuclear threat, the drawbacks are significant: it risks inviting unnecessary suspicion from the international community that South Korea may ultimately be pursuing nuclear armament.

To make matters worse, there are concerns that the government may be making unnecessary and excessive commitments in an effort to avoid the suspicions that the term "nuclear-powered submarine" could generate. It has been reported that the bill announced by the government for legislation on the "Special Act on the Acquisition, Operation, and Safety Management of Nuclear-Powered Submarines" includes, as a basic principle of the program, a provision stating that "the program shall not be intended for the development, manufacture, possession, or use of nuclear weapons, nor shall it engage in any activity that could divert nuclear materials or undermine the credibility of the nonproliferation regime."²³⁾ If our nuclear-powered submarines do not themselves carry nuclear weapons, why should a commitment concerning the development and use of nuclear weapons be incorporated into legislation? South Korea should not repeat, 35 years later, the mistake made by the Roh Tae-woo administration when it voluntarily relinquished E&R capabilities in concluding the Joint Declaration.

In addition, South Korea should proactively prevent North Korea, China, Japan, and other Asian countries familiar with Chinese literary culture from exploiting the term "nuclear-powered submarine" to fuel negative narratives portraying it as a nuclear weapons development program or to amplify suspicions that South Korea is pursuing nuclear weapons development. Given the sensitivity of nuclear-related issues, it would be in the national interest to change the terminology to "atomic-powered submarine" and remove provisions concerning nuclear weapons from the legislation. South Korea needs a more delicate strategic communications approach taking into account external messaging, public image, and symbolism.

1. The Minister further stated that securing enriched uranium as fuel for SSNs would require a separate agreement on military use of nuclear energy, distinct from the existing nuclear cooperation agreement governing civilian use, and that the current nuclear cooperation agreement would also need to be amended to permit enrichment and reprocessing. "[일문일답] 조현 '이란은 공격 인정 안 하겠지만 재발방지 요구할 것'," 『연합뉴스』, 2026년 5월 29일.
2. "盧泰愚 前대통령의 肉聲회고록," 『月刊朝鮮』, 1999년 5월호, p. 132.
3. Kim Jong-hwi, who served as Senior Secretary for Foreign Affairs and National Security at the Blue House at the time, explained that the reason the declaration on the denuclearization and peace policy of the Korean Peninsula was issued in November while the absence of nuclear weapons was confirmed in December was that the withdrawal of U.S. nuclear weapons from South Korea took time. Ibid., p. 135.
4. This section draws on and revises the following work by the author: 전성훈, 『통일한국의 비핵정책: 통일과정에서 통일이후를 바라보며』, 통일연구원, 연구총서 02-01, pp. 101-107.
5. Ibid., p. 103.
6. "김영삼 '미국 北폭격 말린 것 후회'," 『경향신문』, 2011년 9월 5일.
7. 조명균 "북한이 말하는 비핵화, 우리 정부의 비핵화와 차이 있어" 『천지일보』, 2019년 1월 9일.
8. 『서울경제』, 2024년 12월 3일.
9. "정동영 '북핵 30년만 10만배로... 비핵화 앞세운 접근 비현실적'," 『연합뉴스』, 2026년 8월 27일.
10. 전성훈, "북한의 '비핵화 국가전략'과 韓美의 '비핵화 외교'," 『국가전략』, 2019년 제25권 1호, pp. 91-120.
11. "중·러 정상 '대북 제재·압박 반대'... 공동성명서 '비핵화'는 빠졌다," 『연합뉴스』, 2026년 5월 21일; "'비핵화' 빠진 북-중 정상회담…中, 北 관리로 선회한 듯," 『동아일보』, 2026년 6월 9일.
12. 주성하, "김정은과 시진핑의 엄청난 밀약," 『동아일보』, 2026년 7월 14일.
13. 전성훈, "북한에 대한 '핵국가' (Nuclear Power) 호칭을 둘러싼 논란과 대책," 『안보전략 FOCUS』, 한국국방연구원, 2025년 2월 3일.
14. "비핵화 지우는 트럼프 '北에 강력 핵무기 57개'," 『동아일보』, 2026년 8월 21일.
15. "President Donald Trump states North Korea has 57 nuclear weapons," The Chosun Daily, August 21, 2026.
16. 『조선일보』, 『경향신문』, 『한겨레』, 『한국일보』, 2025년 1월 22일.
17. "한미 외교장관 통화 보도자료서도 '北 비핵화' 표현 사라졌다," 『동아일보』, 2026년 8월 26일; "북 비핵화는 한미 일관된 목표... 외교부, 패싱 우려 반박," 『한겨레』, 2026년 8월 28일.
18. 전성훈, "한반도 핵시대에 美 전략자산(Nuclear Triad) 전개의 문제점과 정책대안," 『세종정책브리프』, 2026년 2월 4일.
19. Ibid.
20. "靑 '북미대화 재개 지원...한국 패싱 없도록 한미 공조,'" 『중앙일보』, 2026년 8월 28일.
21. 전성훈, "미국·이란 '이슬라마바드 양해각서(MOU)' 체결: 평가와 시사점," 『세종포커스』, 2026년 6월 26일.
22. "정동영 '북핵 30년만 10만배로... 비핵화 앞세운 접근 비현실적'," 『연합뉴스』, 2026년 8월 27일.
23. "국방부, 핵잠 도입·운영 특별법 입법예고...'연내 제정 목표,'" 『연합뉴스』, 2026년 7월 29일.

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