[US-China Nuclear Deal Special Report] ⑥ Denuclearization Security Initiative for the Korean Peninsula and US-China Cooperation

I. North Korea's Nuclear Development

As of August 2023, North Korea continues its 'frontal breakthrough' strategy. While it attempted the so-called 'Korean Peninsula Peace Process' in 2018-2019, it ended dialogue in October 2019, demanding the prior guarantee of 'development rights' and 'right to survival.' Since the 7th Party Congress's 5th Plenary Meeting in December 2019, it has declared and is pursuing a frontal breakthrough strategy emphasizing self-reliance, ideological struggle, nuclear advancement, and a protracted war.

North Korea has continued its nuclear acceleration, conducting over 70 missile provocations in 2022, including eight intercontinental ballistic missiles (ICBMs), and is engrossed in weapons development in 2023, including the solid-fuel ICBM Hwasong-18. As Kim Jong Un himself declared at the Supreme People's Assembly in September 2022, he is creating an image of not pursuing 'tangible economic living conditions improved by nuclear weapons as a great benefactor.'

North Korea's pursuit of nuclear weapons exhibits the following characteristics. First, it is developing both low-yield and high-yield nuclear weapons. Starting in May 2019, during the Korean Peninsula Peace Process, North Korea began developing the KN-23, capable of carrying low-yield nuclear warheads, which is called the North Korean Iskander. Since then, it has developed approximately 20 types of various missiles, some of which have been deployed. Notably, on March 28, 2023, Kim Jong Un personally supervised the unveiling of the 'Hwasan-31' tactical nuclear warhead, which was announced to be mountable on its 600mm super-large multiple rocket launchers, KN-23, KN-23B, KN-24, new tactical guided weapons, Hwasal-1, Hwasal-2, and nuclear underwater attack drones. The development of ICBMs capable of directly striking the US mainland resumed on March 24, 2022, with the launch of the Hwasong-17, officially withdrawing the previously announced moratorium on test launches. In 2023, it has introduced the solid-fuel-based Hwasong-18, which allows for rapid launches, making detection and identification difficult, can be launched from mobile vehicles, and can carry multiple warheads. In summary, North Korea has effectively deployed low-yield nuclear weapons capable of striking South Korea, Japan, and Guam, and is cultivating its capability to strike the US mainland.

Second, it is institutionalizing its nuclear capabilities. Since Kim Yo Jong's statement on April 15, 2022, declaring the possibility of using nuclear weapons against South Korea in the early stages of a war on the Korean Peninsula, Kim Jong Un personally revealed the two missions of nuclear weapons as the 'April 25 Doctrine' in the same month. In addition to the first mission of military purposes, the second mission allows for their use if 'national interests,' a vague concept, are infringed. In September of the same year, North Korea passed a nuclear law through the Supreme People's Assembly, containing specific nuclear strategies, including five conditions for nuclear use. On November 19, it claimed to have established nuclear operational plans and created and deployed tactical and strategic units accordingly. In March 2023, Kim Jong Un personally supervised a 'simulated comprehensive tactical exercise for nuclear counterattack.' Through this series of actions, North Korea asserts that its nuclear weapons are at a level where they can be used on the actual battlefield and proclaims the legitimacy of its irreversible nuclear possession.

II. Limitations of North Korea's Nuclear Weapons

North Korea's attempts to maximize its nuclear capabilities and institutionalize them to effectively secure the status of a nuclear-weapon state are facing countereffects. First, its economic situation is deteriorating. At the 8th Party Congress in 2021, Kim Jong Un proposed a 1.4-fold increase in GDP over the next five years and reaffirmed this target in his policy speech at the Supreme People's Assembly in September 2022, but achieving it is unlikely. To achieve 140% growth, it needs to grow by 4% annually from 2021 to 2025, which is an impossible figure. Even without the special circumstances of COVID-19, meaningful economic growth is impossible without the lifting of comprehensive UN Security Council and US sanctions that began in earnest in 2016.

The realization of the right to survival and development that North Korea aims for is also being hindered. In the last working-level talks between North Korea and the US in Stockholm, Sweden, in October 2019, North Korea demanded the permanent cessation of ROK-US joint military exercises and the deployment of US strategic assets to the Korean Peninsula as its right to survival, and the lifting of sanctions against North Korea for its development rights. However, as North Korea advances its nuclear and missile capabilities, ROK-US joint exercises become more robust, and state-of-the-art US strategic assets are frequently deployed. Although additional sanctions have not been imposed at the UN Security Council level due to opposition from China and Russia, South Korea, the US, Japan, and the EU have imposed their own sanctions, and sanctions in cyberspace, a source of Kim Jong Un's ruling funds, have been significantly strengthened.

North Korea's nuclear development and aggressive actions continuously worsen inter-Korean political and military relations. For example, the destruction of the inter-Korean Joint Liaison Office in Kaesong Industrial Complex by North Korea in 2020 negatively impacted public opinion in South Korea towards North Korea, particularly among the younger generation. By failing to foster favorable public opinion in South Korea, North Korea is limiting the extent of support that South Korea can provide.

The ROK, US, and Japan are strengthening cooperation against North Korea. Due to historical grievances, ROK-Japan security cooperation has been stagnant or regressing. However, as North Korea advanced its nuclear capabilities in 2022, trilateral security cooperation among the ROK, US, and Japan, led by the US, began in earnest. The 'Phnom Penh Statement on the ROK-US-Japan Trilateral Partnership in the Indo-Pacific,' issued after the ROK-US-Japan summit on November 13, 2022, 'strongly condemned' North Korea's nuclear and missile tests and 'reaffirmed the commitment to the complete denuclearization of the Korean Peninsula,' stating that they would never recognize North Korea as a nuclear-weapon state. As a measure to actually strengthen military deterrence against North Korea, the ROK, US, and Japan also agreed to 'share real-time missile warning information on North Korea.' This goes beyond the ROK-Japan Security Agreement (GSOMIA) to enable real-time joint response to North Korean nuclear and missile threats. Furthermore, ROK-Japan relations, which had been at their worst, are normalizing following the summit between the two countries' leaders in March 2023, driven by the North Korean nuclear threat. Improved ROK-Japan relations and strengthened ROK-US-Japan cooperation enhance deterrence against North Korea's nuclear weapons, acting unfavorably for North Korea.

North Korea's nuclear development is accelerating the development of military nuclear capabilities in South Korea and Japan. While there is no immediate possibility of South Korea and Japan declaring nuclear armament, the possibility of change cannot be ruled out in conjunction with the denuclearization process of North Korea and the global non-proliferation order. For example, if the mainstream US academic community's acceptance of North Korea as a nuclear state, partial denuclearization, and prioritizing the freezing of ICBM launches become a reality, the argument for nuclear armament in South Korea will be significantly strengthened. Furthermore, if Trump's 'America First' policy is revived and fully reflected in foreign policy, the non-proliferation regime built since 1968 could be critically undermined. If Putin's Russia uses nuclear weapons in Ukraine, the effectiveness of the non-proliferation regime, which demands responsible behavior from the five nuclear-weapon states, would effectively vanish. In such a situation, if North Korea continues to advance its nuclear capabilities, South Korea and Japan may pursue nuclear capabilities. Although nuclear armament in South Korea and Japan would take time, their overwhelming technological, economic, and conventional military superiority over North Korea would rapidly diminish the significance of North Korea's nuclear possession.

The new Cold War order that North Korea anticipates is unlikely. Putin's war in Ukraine has paralyzed the UN Security Council, but it has also served as an opportunity for the core allies of liberal democracy, led by the US, to reunite. Particularly, as North Korea aligns with Russia, the argument against lifting sanctions has been strengthened. With European countries imposing sanctions on Russia unanimously over ten times, lifting sanctions without proactive denuclearization measures by North Korea has lost its justification. More fundamentally, the confrontation between North Korea, China, and Russia versus South Korea, the US, and Japan at the regional level, and the confrontation between liberal democracies and authoritarian states at the global level, cannot guarantee the same longevity as the Cold War. This is because there is a lack of ideological coherence against liberal democracy, and neither internal cohesion within blocs nor insulation between blocs is guaranteed. Although the US and China are in conflict, complete decoupling in the economy and various other fields, unlike the US-Soviet Cold War, is impossible. There is also a lack of values that unite authoritarian regimes within blocs, and regionalization phenomena emerge rather than bloc formation. Bilateral relations such as North Korea-China, North Korea-Russia, and China-Russia have historically been based on convenience rather than values and ideology, and this remains true today. Therefore, while short-term cooperation against a common enemy like the US is possible, guaranteeing its sustainability is difficult. If the US and China engage in 'exploration and adjustment' and strategic competition becomes institutionalized to a certain extent, North Korea's room for maneuver will further shrink.

In conclusion, despite North Korea's seemingly unhindered nuclear acceleration, it faces severe repercussions. The situation where North Korea is recognized as a de facto nuclear-weapon state, which it aims for, is not easily attainable. Instead, as time passes, the utility of North Korea's nuclear weapons will decrease, and its economy will worsen, increasing the likelihood of facing internal challenges. South Korea must maximize the dynamics between the US and China under a policy objective of making North Korea abandon its nuclear weapons and prioritize its economy.

III. North Korea's Nuclear Weapons and US-China Relations

North Korea is not only developing tactical nuclear weapons but also acknowledging the necessity of nuclear combat operational strategies and is preparing specific measures for military options, as mentioned at the Party Central Military Commission in April 2023 (<Rodong Sinmun> 2023). The North Korean nuclear issue can be exacerbated by military and political crises at the Korean Peninsula level, and the issue of other conflicts in the Indo-Pacific region developing in parallel with the North Korean nuclear threat also arises. Failure to manage the North Korean nuclear crisis or the escalation of crises from other regions to the Korean Peninsula could lead to an uncontrollable situation.

Figure 1. Missile Launch Trends During the Kim Jong Un Era Figure 2. Estimated North Korean Nuclear Arsenal Size

(Source: https://isis-online.org)

If the North Korean nuclear issue is left unaddressed, it could lead to outcomes undesirable for both the US and China. The advancement of North Korea's nuclear capabilities could be a factor that creates another high-intensity crisis on the Korean Peninsula during a Taiwan crisis, which neither the US nor China desires. Furthermore, if the continuous advancement of North Korea's nuclear capabilities is left unchecked and the credibility of US extended deterrence on the Korean Peninsula weakens, it could lead to a chain reaction of nuclear proliferation to South Korea and Japan. Therefore, managing stability on the Korean Peninsula during a high-intensity US-China crisis and maintaining a regional non-proliferation regime to resolve the North Korean nuclear issue are crucial matters for both the US and China.

Furthermore, the US pursuit of integrated deterrence and its global posture review are driving changes in US-China relations and are linked to the North Korean nuclear issue, necessitating a detailed strategy. The US is strengthening its defense posture based on the new concept of integrated deterrence, while China views the strengthening of the alliance system due to US integrated deterrence as a phenomenon that exacerbates the international security environment.

The issues that could arise from the lack of US-China cooperation on the North Korean nuclear problem include the possibility of a chain reaction of nuclear development in Northeast Asia, the potential for a Taiwan crisis to spill over to the Korean Peninsula, and the intensification of US-China military competition and the increase of the North Korean nuclear threat. It is time to consider the possibilities and methods of US-China cooperation on these issues.

IV. Pursuing US-China Compromise for North Korean Denuclearization

The advancement of North Korea's nuclear capabilities encroaches upon the interests of China as well as the US. Above all, if the advancement of North Korea's nuclear capabilities is not deterred and its nuclear posture is not shifted to a defensive stance, it could ultimately lead to nuclear armament in the Korean Peninsula and Northeast Asia. Over 70% of South Korean citizens support nuclear development, according to a public opinion poll (Ahn 2022). Of course, such a high response may reflect low anti-nuclear public opinion in Japan, but the breakdown of denuclearization negotiations and bleak prospects for resuming talks are factors that lead South Korean opinion leaders and the general public to sympathize with the argument for nuclear development. Even Japan, which adheres to the three principles of nuclear non-possession, non-production, and non-introduction, has shown trends toward considering the redeployment of nuclear weapons or nuclear sharing due to China's nuclear capabilities and North Korea's nuclear development. In early 2022, former Prime Minister Shinzo Abe mentioned that Japan should consider nuclear sharing with the US (Johnson 2022). While Japan's public opinion on nuclear development reached 75% as of 2019, and Prime Minister Kishida is a politician who opposes nuclear possession or sharing (Deacom and Soligen 2023), Japan, along with Germany, is classified as an 'insurance hedger' country prepared for nuclear development if necessary (Narang 2022, 74).

China will also feel burdened by the strengthening of the ROK-US alliance and the US-Japan alliance due to North Korea's nuclear armament. South Korea is increasingly relying on US extended deterrence to cope with the North Korean nuclear issue, and the ROK-US alliance has been further strengthened. This is evident in the Washington Declaration announcing the establishment of the Nuclear Consultative Group, as well as the message released by Presidents Yoon Suk Yeol and Biden that they would begin discussions on applying the ROK-US alliance to cyber and space domains. The cooperation on extended nuclear deterrence between the ROK and the US due to the North Korean nuclear threat can be expanded to cooperation in various other fields for integrated deterrence. Prior to this, Japan also discussed measures to respond to North Korea's nuclear and missile issues and China's security threats at the ROK-US-Japan '2+2' Foreign and Defense Ministerial Meeting (January 11, 2023). Despite these deterrence efforts, when North Korea test-fired the long-range rocket Chollima-1 on May 31, 2023, the defense ministers of the three countries agreed to establish and operate a real-time sharing system for missile warning information on North Korea among the ROK, US, and Japan. The joint statement from the ROK-US-Japan summit in November 2022 proposed measures to strengthen cooperation for nuclear deterrence against North Korea. In the past, China had expressed concern about the strengthening of the ROK-US alliance since the launch of the Yoon Suk Yeol administration, and the North Korean nuclear threat is becoming a factor that realizes such concerns (<Dailyan> 2022).

If North Korea's nuclear development is left unchecked, threats of nuclear use will occur frequently in the near future, and the US and China could inadvertently become involved in a North Korean-initiated nuclear crisis. Above all, the US cannot avoid responding to a nuclear crisis in accordance with its extended deterrence commitment, and China cannot avoid responding in some way to the strengthening of US nuclear capabilities around the Korean Peninsula amidst US-China competition. A representative example showing this possibility is that after the Cheonan incident, China reacted with tension and conducted counter-exercises such as simultaneous firing drills in response to ROK-US joint exercises that mobilized US aircraft carriers to deliver a warning message to North Korea. China now possesses three aircraft carriers and may show a tendency to counter US actions. Due to the intertwined relationship between the North Korean nuclear issue and the US-China rivalry, a nuclear crisis poses a continuous risk of involvement for both the US and China.

Furthermore, it is an awkward situation that China is finding it difficult to exercise leadership in the global non-proliferation regime as a result of not adequately condemning the North Korean nuclear issue. Since its first nuclear test, China has called for a global summit to eliminate nuclear weapons and has advocated for nuclear disarmament within the framework of the NPT. For China to allow North Korea, which is pursuing nuclear development in violation of its denuclearization commitments, to continue its actions is inevitably a burden on its traditional diplomatic values.

North Korea emphasized its rights to development and survival in the context following the Hanoi 'No Deal' situation. The US and China can agree on denuclearization through negotiations where they provide North Korea with the rights and regime security it demands, instead of North Korea's denuclearization. During the Biden administration, the US has pursued unconditional dialogue with North Korea and explored possibilities for dialogue. China has recently favored solutions such as 'dual suspension' and 'dual track approach,' and as demonstrated during Xi Jinping's visit to China in June 2019, a solution for North Korean denuclearization through regime security.

a. Policy Direction

US-China non-proliferation cooperation in Northeast Asia, under the condition of North Korea's continued nuclear capability advancement, involves both the US and China jointly pursuing measures to prevent nuclear proliferation in the region. Of course, the Washington Declaration, centered on the ROK-US alliance, is also such a measure, albeit unilaterally by the US. In the recent Washington Declaration between the ROK and the US, the US pledged to further strengthen extended deterrence for allies like South Korea. Accordingly, the US has expanded the deployment of strategic assets to the Korean Peninsula and initiated the activities of a nuclear consultative body to regularly consult with South Korea on extended deterrence. However, if North Korea's nuclear capability advancement continues, the possibility of redeploying US nuclear weapons to the Korean Peninsula cannot be ruled out. While the Washington Declaration does not address the redeployment of nuclear weapons to the Korean Peninsula, if North Korea's nuclear capability advancement continues, redeployment of nuclear weapons could become a possibility to strengthen extended deterrence. A future where deterrence against North Korea is strengthened primarily by the US would also be disadvantageous for China. Therefore, there is a need to present a new approach where the US and China jointly provide security guarantees to non-nuclear states in Northeast Asia and strengthen the non-proliferation regime.

Nuclear proliferation in Northeast Asia should be prevented more stably through an international, multilateral approach. The Biden administration has adopted an approach to resolve the possibility of nuclear proliferation by providing renewed security guarantees of extended deterrence to its allies through the Washington Declaration. However, given the uncertainty of US domestic politics, there is no guarantee that the US government's approach will be maintained. In particular, former President Trump has shown a negative view of defense spending for allies like South Korea and has demanded that allies bear more of the costs for their defense. If the reliability of extended deterrence to South Korea and Japan weakens due to factors such as a change in administration, various countries in Northeast Asia may sequentially choose nuclear development. To prevent such a situation, measures to prevent nuclear proliferation in Northeast Asia or East Asia should ideally be carried out in an international and multilateral manner.

In terms of content, it is necessary to establish a system that provides passive security assurances to non-nuclear states. For North Korea, deterring nuclear use and future denuclearization are objectives pursued by the international community, and for South Korea, Japan, and further, Taiwan, non-proliferation of nuclear weapons is included. To this end, if a multilateral non-proliferation regime is established in Northeast Asia, it should be designed to address these various issues. First, it could provide passive security assurances to South Korea and Japan at the P-5 level. As with nuclear-weapon-free zone treaties, P-5 countries could pledge not to use nuclear weapons against signatory states. Second, at the regional security level, member states can urge North Korea towards denuclearization and condemn its nuclear capability advancement measures. Simultaneously, to guide North Korea toward denuclearization, it should be allowed to obtain membership status, receiving passive security assurances from the P-5, if it abandons its nuclear weapons. Additionally, although it may be secondary, while the risk of North Korean nuclear weapons remains, the Northeast Asian non-proliferation regime should support efforts to strengthen US extended deterrence.

b. Implementation Measures

To establish a regional non-proliferation regime in Northeast Asia, efforts are needed to publicize the elimination of nuclear threats to South Korea and Japan. One method of publicizing this could be for high-level officials to request attention to the seriousness of the Northeast Asian nuclear issue through congratulatory speeches at large-scale nuclear policy conferences. Subsequently, the foreign ministers of each country could issue statements expressing the urgent need to eliminate nuclear threats to their respective countries and proposing a meeting to discuss this matter. Then, through the convened meeting, a phased proposal could be made to establish an organization to discuss security assurances for the elimination of nuclear threats to South Korea and Japan.

To establish such a regional non-proliferation regime, it is also necessary to pressure China to accept multilateral negotiations. It is important for China to understand that without security assurances for South Korea and Japan, nuclear proliferation in Northeast Asia will occur in some form. To this end, South Korea could pursue the early revision of the ROK-US Atomic Energy Agreement in consultation with the US, and establishing a cooperative system to expand cooperation in nuclear technology between South Korea and Japan would be another method. In this way, China can be guided to discuss measures to prevent nuclear development in South Korea and Japan through means that do not pose a threat to them.

Consequently, a Northeast Asian security/non-proliferation regime where the US and China jointly provide security assurances to non-nuclear states in Northeast Asia can induce North Korea to believe that it can receive security assurances through this system. If so, the Northeast Asian regional non-proliferation regime could serve as an opportunity to draw North Korea towards denuclearization. If this regime also includes elements that encourage economic exchange and cooperation among non-nuclear states in the region, such as North Korea, Japan, and South Korea, it could also satisfy North Korea's demand for development rights.

V. Cooperation for Stability on the Korean Peninsula during a Taiwan Crisis

If a Taiwan crisis escalates into a high-intensity conflict, US experts also express concern that China may create tensions on the Korean Peninsula through North Korea. Some experts distinguish between high-intensity crises that could occur in the Taiwan region as Chinese joint firepower operations, maritime blockades of Taiwan, and clashes during a full-scale invasion of Taiwan. They speculate that if the last scenario, an invasion, materializes, China would have a reason to create tensions on the Korean Peninsula by coordinating with North Korea. They argue that if North Korea's provocations against the South are low- or medium-intensity, South Korea would need to respond independently (Saunders 2023). From this US perspective, it can be predicted that China might encourage North Korean provocations on the Korean Peninsula during an invasion to create unfavorable conditions for the deployment of US ground forces. In reality, if North Korea provokes on the Korean Peninsula amidst a Taiwan conflict, the repercussions are expected to be greater than anticipated. If North Korea provokes during a Taiwan crisis, it could also heighten tensions in Japan, similar to when the Hwasong-12 missile test-fired on October 4, 2022, passed over the Japanese archipelago. Additionally, North Korea's provocations using new means, such as underwater nuclear weapons, could occur. In such cases, the support capacity of Japan and South Korea, which would indirectly support the US involved in the Taiwan crisis by escalating tensions on the Korean Peninsula, is predicted to significantly decrease.

On the other hand, there is an analysis that not only the US but also China would be concerned about simultaneous crises occurring in multiple locations. It is argued that China has organizational limitations in conducting military operations simultaneously in various dispersed regions. With land borders with 14 countries and maritime borders with 7 countries, China's territorial disputes with various countries such as Japan, India, the Philippines, and Vietnam are internal sources of tension that cause resource competition between multiple theaters. For example, since the early 1990s, the Chinese military has designated war with Taiwan as its top priority scenario, but various conflicts have prevented China from focusing solely on the Taiwan issue. For instance, in mid-2020, due to the Sino-Indian conflict, the Chinese military had to move a quarter of its army to the west and conduct training for several ground attack and missile brigades, but these trainings were of a type that did not contribute at all to operations related to Taiwan (Wuthnow 2022). In addition, North Korea and Afghanistan, while not in conflict with China, are unstable countries that could create situations the Chinese military must prepare for. Furthermore, overseas US forces in the Korean Peninsula, Japan, etc., are also forces that the Chinese military must guard against. In addition, China is concerned that neighboring countries may use a Taiwan crisis to reclaim territory or achieve a favorable resolution of disputes. That is why Mao Zedong emphasized that issues beyond the main direction of attack should not be overlooked (Wuthnow 2022, 91). Consequently, China may perceive a conflict on the Korean Peninsula during a Taiwan crisis as a factor that prevents it from concentrating resources on the Taiwan front.

a. Policy Direction

Logically, the concern about North Korean provocations during a Taiwan crisis stems primarily from the risk that China may exploit North Korean provocations or that North Korea may engage in adventurous provocations using the Taiwan crisis. Therefore, to prevent a crisis on the Korean Peninsula during a Taiwan crisis, it is necessary to alleviate concerns regarding these two factors.

However, if China also determines that simultaneous conflict occurrence could hinder the realization of its policy objectives toward Taiwan, it may focus on the factor of crisis occurrence on the Korean Peninsula due to North Korea's adventurism. It is necessary to address the possibility of opportunistic provocations that North Korea might pursue during a US-China conflict in the Taiwan region. For example, North Korea could employ coercive strategies based on its nuclear capabilities against South Korea at a future point when some of the US Forces Korea are redeployed to the Taiwan region. In reality, North Korea is an actor that has pursued adventurous foreign policies that are difficult for the US and China to understand. Therefore, it is highly likely that both Beijing and Washington will agree when the necessity of discussing the issue of conflict escalation due to North Korea's adventurism is raised. Thus, US-China cooperation focused on uncontrollable conflict issues caused by North Korea can be considered.

First and foremost, it is crucial to establish a consensus between the US and China on preventing the escalation of crises during a Taiwan crisis and to activate military channels for preventing escalation even during a Taiwan contingency. As of July 2023, discussions have not taken place between the US and China regarding the Taiwan situation, and China is refusing high-level dialogue in the defense sector with the US, citing sanctions against its Minister of National Defense. However, the absence of such US-China defense dialogue does not help in addressing the complex issues that may arise during a Taiwan crisis. Considering the war in Ukraine, there was an implicit consensus between NATO and Russia after the outbreak of the war not to expand it beyond Ukraine's borders. Based on this, a deconfliction hotline channel was established between the US European Command and the Russian National Defense Management Center in March 2022, after the outbreak of the war in Ukraine (Stewart and Ali 2022). Even during the collision between a US drone and a Russian fighter jet in March 2023, high-level channels between the US and Russia were activated (Stewart and Ali 2022). Considering the example of the war in Ukraine, securing an early consensus on preventing escalation and deconfliction that could lead to escalation, and immediately establishing hotlines and military channels during a crisis, are important factors for successful de-escalation.

b. Implementation Measures

China, even to prepare for future US-China conflicts, is accumulating lessons from the war in Ukraine. Based on this experience, it can be persuaded that efforts should be made to manage unpredictable variables such as North Korean provocations and to prevent the escalation of US-China conflicts. Just as China analyzed the 1991 Gulf War and developed the concept of information-based warfare and implemented it as actual military strategy, it is expected to analyze Western military strategies revealed after the war in Ukraine and develop related military strategies. The results of this analysis will undergo several stages of review but will ultimately be approved by the highest leadership in China and reflected in China's foreign and military strategies. In this regard, it is noteworthy that Chinese experts thoroughly refer to Western research materials and analyses, so China's analytical results also converge technologically with those of Western research, including the US. Based on this prospect, to make China learn the necessity of preventing escalation, it is necessary for US government agencies or experts, and South Korean government agencies and experts, to emphasize successful de-escalation as a lesson from the war in Ukraine and present methods for it. This issue should also be emphasized in 1.5-track expert meetings to encourage China's interest in this matter.

Through this, after inducing China's basic interest in US-China military dialogue, the US should directly propose and discuss measures for regional stability management during a Taiwan crisis through official, albeit private, meetings. Of course, the US may feel burdened by directly discussing the Taiwan issue with China. This is because China will use the 'One China' principle agreed upon by the US and China as an opportunity to criticize US efforts to defend Taiwan. However, given that China does not rule out the use of force against Taiwan, raising the necessity of managing unpredictable variables in the Indo-Pacific region, such as North Korean adventurism, during a Taiwan crisis will not be a burden to US efforts to defend Taiwan. China may also consider this a favorable agenda for itself, as it can avoid situations disadvantageous to its own interests. Managing North Korean adventurism during a Taiwan crisis is a matter of common interest for both the US and China.

To pursue the aforementioned matters, the South Korean government first needs to discuss the role of the ROK-US alliance during a Taiwan Strait crisis with the US. While the US Forces Korea may not be the primary force utilized during a Taiwan Strait crisis due to their force structure and objectives, various situations may arise depending on the nature, development, and scale of the conflict. The US considers the Indo-Pacific as a single theater and can utilize all forward-deployed forces, including US Forces Korea and US Forces Japan, in regional conflicts. Due to the nature of their forces, US Forces Japan are expected to be prioritized during a Taiwan Strait crisis, but if the US-China conflict front expands, US Forces Korea, which are close to mainland China, could also be mobilized. For example, Camp Humphreys, a US military base located 800 km in a straight line from Beijing, serves as a bridgehead to block China's advance into the Pacific. South Korea needs to set its desired final objectives during a Taiwan Strait crisis, identify areas where it can contribute as an alliance and areas where it cannot, and then concretize them to some extent through consultations with the US. In particular, the possibility of a Taiwan Strait crisis being linked to a Korean Peninsula crisis should be considered, and corresponding alliance-level responses should be prepared. Based on the agreed-upon plan between the ROK and the US, efforts should be made to prevent the Taiwan Strait crisis from being linked to the situation on the Korean Peninsula through dialogue with China.

VI. Deriving Cooperation with China Using US 'Integrated Deterrence'

The North Korean nuclear issue can become an uncontrollable variable during US-China conflict in the Indo-Pacific region. The US is strengthening its overall defense posture in line with the concept of integrated deterrence, which maximizes deterrence by combining various capabilities to counter China's advanced and growing military power (The White House 2022). In response, China is accelerating the construction of intelligent military capabilities while emphasizing its traditional information-based warfare strategy. At the 20th National Congress of the Communist Party of China in October 2022, President Xi Jinping emphasized the need to develop military strategy based on the 'laws of information-based and intelligent warfare' (People's Daily Online 2022). In particular, the transformation of military capabilities in accordance with the US's integrated deterrence and Global Posture Review (GPR) can become a key means for the US to secure relative superiority in the US-China conflict process, and consequently, it can elicit China's cooperation in driving North Korean denuclearization.

US integrated deterrence can be defined as assuming the Indo-Pacific as a single theater and maximizing the utilization of assets by linking NATO allies in the Atlantic with allies in the Indo-Pacific region (Park Won-gon 2022). Specifically, the US emphasizes cooperation with allies in various domains or multi-domain battlefields such as 'airspace, maritime, space, and cyberspace.' Through integrated deterrence, the US expects to promote not only the linkage between the US and its allies but also cooperation among the allies themselves. For shared security objectives, ultimately the common goal of containing China, the US hopes that its allies and friendly nations will contribute to integrated deterrence according to their respective wills and capabilities. Deputy Secretary of Defense Kathleen Hicks expressed this as a 'federated' approach to regional security, emphasizing the integration of logistics, intelligence, etc., with allies (2021). Other key concepts for integrated deterrence include 'deterrence by denial,' 'resilient deterrence,' and 'deterrence by cost imposition' (Department of Defense 2022). While various interpretations are possible, it implies imposing immense costs on adversarial or competitor nations through regional arms races. Since the US utilizes its established alliance network, China or North Korea, as a single target country or through so-called North Korea-China-Russia cooperation, faces limitations in countering US integrated deterrence.

The Global Posture Review aims to move away from Cold War-era force deployments and maximize flexibility to concentrate on regions reflecting vital interests. Although initiated during the George W. Bush administration, its progress was somewhat deferred due to the War on Terror, and it was fully launched by then-Secretary of Defense Mark Esper during the Trump administration. The Biden administration also ordered a review at the beginning of its term, and the results were announced in November 2021, but the publicly released information was very limited. The core idea is to re-examine force deployments to compete with China, emphasizing speed and connectivity. Specifically, it proposes securing 'depth connected to a much wider and more diverse range of regional locations, regenerability to recover from preemptive attacks, agility to deploy forces most appropriately at specific times and places, and redundancy to ensure replenishment even if forces in one location are completely lost' (Kim Dong-hyun 2020). In other words, it can be interpreted as maximizing the efficient use of forward-deployed US forces overseas to deploy maximum force in the shortest possible time when necessary, while further strengthening connectivity with allies.

Although there are limitations to the US developing integrated deterrence and global posture review,[1], it is likely to continue regardless of future changes in the US administration, as it is being pursued by the Democratic Biden administration as well as the Republican Trump administration. If it continues to develop, it will enhance overall capabilities to respond to threats, including North Korea, in addition to its primary objective of containing China.

China will also strengthen its military in response, but it is unlikely to reach a level comparable to the US, which achieves synergistic effects by integrating with its allies. Although China is linked with North Korea through an alliance, it cannot maintain the same level of interoperability and readiness as treaty allies of the US, especially South Korea. In response to US-led integrated deterrence, China will improve its self-defense capabilities through intelligent warfare, but it will be insufficient to counter the US, which has treaty alliances with over 50 countries. Therefore, China may react negatively to North Korea's nuclear acceleration, which provides justification for strengthening integrated deterrence, as it feels the limitations of an arms race with the US and its allies.

a. Policy Direction

South Korea must actively participate in the integrated deterrence and global posture review pursued by the US to secure an advantage and, based on this, pressure China to create cooperation for North Korean denuclearization. To this end, South Korea must first refine its grand strategy. South Korea's strategy in the context of US-China conflict and its linkage to North Korean denuclearization must be established. In broad terms, South Korea should seek co-evolution with the US and China, while also considering responses to changes in the strategic situation. In particular, attention should be paid to the recently much-discussed 'peak China' theory (Nye 2023; Brands and Beckley 2022; Brooks and Wohlforth 2023; Park Won-gon 2023). China faces increasing burdens due to declining birth rates and an aging population, while the US gains a million working-age individuals annually. China's dependence on foreign capital is 75% for oil, whereas the US became the world's largest exporter of liquefied natural gas (LNG) in 2021. Unlike China, which is losing efficiency across its society and economy due to the reinforcement of a one-person rule system, the US, despite suffering from democratic polarization, guarantees freedom of intervention, enterprise, and organization. China's economy has achieved economic growth in recent years through large-scale government-led capital investment, but the possibility of it falling into recession due to excessive debt cannot be ruled out. In contrast, the US surpasses China in high productivity, low unemployment, leadership in high-tech industries, and dollar hegemony. Militarily, the US enjoys a stable security environment, while China is in border disputes with India, Japan, Vietnam, the Philippines, and others. In terms of overseas power projection, the US has secured over 750 bases worldwide, while China operates only one in Djibouti, indicating a significant gap.

Therefore, despite the remaining uncertainties about the future, the US still has a high probability of gaining an advantage in its competition with China. In this situation, if integrated deterrence and global posture review develop, China is likely to eventually compromise with the US to some extent, so South Korea should prepare a strategy considering this and link it to North Korean denuclearization. In particular, it is necessary to highlight that North Korea's nuclear development is one of the driving forces increasing the consensus and necessity for integrated deterrence and US force realignment. Most countries participating in integrated deterrence, including those directly exposed to the North Korean nuclear threat like South Korea and Japan, oppose North Korea's possession of nuclear weapons. China should be pressured to feel burdened by the integrated deterrence pursued by the US and its allies, thereby cooperating in resolving the North Korean nuclear issue, which provides justification for strengthening integrated deterrence.

b. Implementation Measures

Primarily, South Korea must actively participate in integrated deterrence and global posture review to enhance its readiness and expand its deterrence capabilities against North Korea. Separate from the long-term competition between the US and China, the immediate task from South Korea's perspective is to increase its response capabilities to the existing North Korean nuclear threat. If the Atlantic NATO alliance and the 'hub-and-spoke' alliances in the Indo-Pacific region are linked, the number of adversaries North Korea must face will geometrically increase. Currently, North Korea is deterred by the ROK, US, and Japan. If NATO's 31 member states cooperate, North Korea will have to confront a massive military coalition, even with China's support. The utility of North Korea's nuclear weapons will rapidly diminish. South Korea must recognize NATO's new Strategic Concept adopted in 2022 and meticulously establish cooperation goals, scope, and levels. Furthermore, it is necessary to set and concretize the final stages of cooperation with key US allies in the Indo-Pacific region, such as Japan and Australia.

VII. Conclusion

This report has presented the current status and limitations of North Korea's nuclear development, the problems that could arise from the North Korean nuclear issue amidst US-China competition, and proposed countermeasures for proliferation in Northeast Asia due to North Korea's continuous nuclear development, heightened tensions on the Korean Peninsula during a Taiwan crisis, and China's lack of cooperation on North Korean nuclear issues amid intensifying US-China military competition. Pursuing a 'Korean Peninsula Denuclearization Security Initiative' that begins with a non-proliferation regime in Northeast Asia by maximizing the potential for mutual cooperation between the US and China on the existing threat of North Korean nuclear weapons is necessary. Furthermore, cooperation should be sought to maintain stability on the Korean Peninsula in the event of a heightened Taiwan crisis. Strengthening integrated deterrence, including the ROK-US alliance, can also be a way to increase the cost of confrontation for China and North Korea, thereby eliciting their cooperation.

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[1] For details, refer to Park, Won Gon, “The U.S. Indo-Pacific Strategy and the ROK-U.S. Alliance: Integrated Deterrence and Global Posture,” 『Korea National Strategy』, Issue No. 19 (July 2022), pp. 38-40.

Park, Won Gon_Director, North Korea Research Center, East Asia Institute. Professor, Department of North Korean Studies, Ewha Womans University.

Lee, Jung Gu_Research Fellow, Korea Institute for Defense Analyses

■ Managed and Edited by:Park, Ji Soo, EAI Researcher

    Inquiries and Editing: 02 2277 1683 (ext. 208) | jspark@eai.or.kr