The recent incident of a North Korean warship sinking in May 2025 not only highlights the challenges faced by DPRK in strengthening its military capabilities, but also serves as a metaphor for the broader crisis on the Korean Peninsula. In recent years, against the backdrop of the breakdown in U.S.-North Korea dialogue, heightened tensions between South and North Korea, and the Russia-Ukraine conflict, the security situation on the Korean Peninsula has grown increasingly precarious. With the Trump 2.0, coupled with new political developments in South Korea and the evolving U.S.-Russia relationship, maintaining peace and stability on the Korean Peninsula and in Northeast Asia faces unprecedented complexities.

According to US intelligence estimate, North Korea may resume nuclear testing. In Marh 2025, US Director of National Intelligence Tulsi Gabbard warned, "North Korea is probably prepared to conduct another nuclear test on short notice and continues to flight-test its ICBMs to demonstrate their increasing capabilities as leverage in future negotiations." However, the policy direction of the Trump 2.0 upon the North Korea remains unclear. President Trump often mentioned North Korea as a “nuclear power.” Trump’s strikes on Iranian nuclear facilities and the regime change element in America’s overall thinking would have complicated implications on North Korea.

In the meantime, South Korea's new president, Lee Jae Myung is expected to tackle several intertwined crises including Trump’s tariff war and increasing US-China rivalry. The Lee Jae Myung administration is likely to see a “perfect storm” on the Korean Peninsula. However, we should not give up efforts to ease tensions and avoid conflicts in Asia. This October, South Korea will host the APEC Leaders’ Meeting. In this context, relevant countries including China, must engage in strategic communication to explore pathways for preventing major crises on the Korean Peninsula.

Avoiding the Repetition of Dysfunctional Dialogue

We need to learn lessons from the previous failed diplomatic interaction between the U.S. and North Korea. During Trump’s first term, U.S.-North Korea relations underwent dramatic shifts. After taking office in January 2017, Donald Trump and Kim Jong-un, North Korea’s leader, exchanged nuclear threats. In September 2017, North Korea conducted its sixth nuclear test. In 2018, Trump and Kim Jong-un met in Singapore, where North Korea sought complete denuclearization of the Korean Peninsula in exchange for U.S. concessions, including sanctions relief and security guarantees. The U.S. demanded that North Korea abandon its nuclear weapons and programs "completely, verifiably, and irreversibly" (CVID), while North Korea emphasized "denuclearization of the peninsula" (which would involve the U.S. nuclear umbrella over South Korea) and "comprehensive denuclearization," expressing reservations about "verifiable" and "irreversible" measures.

Clearly, Washington and Pyongyang had significant disagreements over the end state, timeline and roadmap for denuclearization. Mutual distrust, particularly at the bureaucratic level, also posed major obstacles to sustaining dialogue and implementing agreements. Both Donald Trump and Kim Jong-un faced domestic political constraints. For instance, John Bolton, a hardliner national security advisor to Trump, believed that Kim Jong Un has no intention of abandoning his nuclear programs. The failure of the 2019 Hanoi summit between the U.S. and North Korea appears to have triggered a fundamental hardening of North Korea’s stance.

In 2021, North Korea announced a five-year military modernization plan at the Eighth Congress of the Workers’ Party. It decided to accelerate the nuclear arsenal development in 2022, calling its nuclear power status irreversible and nonnegotiable. In 2023, North Korea amended its constitution to formally enshrine its status as a nuclear-armed state. According to the “World’s Nuclear Warheads Data” 2025 report released by Nagasaki University’s Research Center for Nuclear Weapons Abolition, North Korea may now possess about 50 deployable nuclear warheads.

The Triangle of Upheavals

The failure of US-North Korea summit during the Trump first term is not the only thing making the situation on the Korean peninsula more tense. In past few years, North Korea has capitalized on shifting international dynamics to bolster its nuclear and conventional military capabilities, seek recognition as a nuclear state, and improve its economic situation. The factors including domestic politics, major power rivalry and global security hotspots form a triangle of upheavals, which exacerbate tensions on the Korean peninsula.

First, the hostility of South Korea’s Yoon Suk-yeol administration towards North Korea has been exploited. Against the backdrop of fierce clashes between conservative nationalism and progressive nationalism, South Korea’s domestic politics have taken a sharp rightward turn. The Yoon administration has shown no interest in inter-Korean dialogue while prioritizing the strengthening of the U.S.-South Korea alliance and trilateral cooperation with the U.S. and Japan. Enhanced U.S.-South Korea military exercises and trilateral military collaboration have heightened North Korea’s sense of insecurity. By late 2023, Kim Jong-un began characterizing inter-Korean relations as between "two hostile states," signaling a rupture with South Korea and even hinting at the potential use of tactical nuclear weapons against it. North Korea also stated that its underwater drone could unleash a "super-scale radioactive tsunami" to destroy enemy warships.

Second, the Russia-Ukraine conflict became a catalyst for tension on the Korean peninsula. International media have followed military cooperation between North Korea and Russia, as the two countries deepen their "comprehensive strategic partnership." Some experts even argue that North Korea has acquired advanced military technologies from Russia, including nuclear-powered submarine, intercontinental ballistic missiles, and reconnaissance satellite capabilities. They warn that this could embolden North Korea’s adventurism and alter the military balance on the Korean Peninsula and in Northeast Asia. Meanwhile, South Korea is also deeply involved in the Russia-Ukraine conflict. It has provided significant military aid to Ukraine and NATO. South Korea signed a $14 billion arms deal with Poland in 2022, and considered establishing military-industrial production bases in Europe. These developments have extended the ripple effects of the Russia-Ukraine conflict into Northeast Asia.

Third, America’s new Cold War against China has brought diplomacy surrounding the situation on the Korean Peninsula to a standstill. Many Chinese analysts believe that the U.S. seek to take advantage of the tensions on the Korean Peninsula to strengthen its latticework coalition vis-à-vis China. Since Trump’s first presidency, the U.S. has intensified strategic competition with China, making diplomatic efforts on the Korean Peninsula issues between these two giants increasingly difficult. As noted by Professor Chun Chaesung of Seoul National University, since the breakdown of the 2019 Hanoi talks, Pyongyang has reoriented its national strategy by combining self-reliance with a “new Cold War” strategy. While China has strictly enforced UN Security Council sanctions on North Korea, the U.S. has repeatedly accused China of non-compliance. Controversial U.S. actions on Taiwan, including Speaker Nancy Pelosi’s visit, the AUKUS nuclear submarine pact, and plans to deploy land-based intermediate-range missiles in the Philippines are China’s major concerns, which have severely undermined U.S.-China coordination on the Korean Peninsula issues.

Comprehensive Recalibration Needed

Blaming North Korea alone for the tensions on the Korean Peninsula is one-sided. Amid mutual distrust and an escalating arms race, achieving denuclearization has become increasingly difficult. Some experts even argue that the focus should shift to nuclear arms control and preventing nuclear war. The crisis must be examined through a structural lens of "domestic politics-great power rivalry-global security challenges" to identify potential solutions.

First, the trajectory of the Trump administration’s Indo-Pacific strategy and its stance on North Korea’s nuclear program are critical. On the nuclear issue, the U.S. appears to have shifted from "strategic patience" to "strategic indifference." Many believe the Trump administration has abandoned the goal of denuclearization. Some U.S. strategists argue that the severity of the North Korean nuclear threat could incentivize allies like South Korea and Japan to assume greater security responsibilities and strengthen trilateral alliances. In Trump’s second term, the influence of the "prioritizer" in the foreign policy circle has grown, advocating for reduced U.S. overseas intervention and a more transactional foreign policy. Before taking office, U.S. Under Secretary of Defense for Policy Elbridge A. Colby voiced support for South Korea’s nuclear armament. His "strategy of denial" focuses on conflicts with major powers like China and Russia, suggesting North Korea’s nuclear issue is not a top priority for the Trump administration. The Trump administration is advancing a record $1 trillion military budget, modernizing nuclear weapons, and developing the Golden Dome missile defense system. In addition, under America’s leadership, the NATO is also upgrading its nuclear arsenal, treating China and Russia as potential nuclear adversaries. These military-first moves risk fueling an arms race and undermining strategic stability among the U.S. and China. Against the collapse of U.S.-Russia nuclear arms control and U.S. double standards on non-proliferation evidenced by the AUKUS, denuclearization of the Korean Peninsula will grow even more elusive.

Second, China faces growing challenges in addressing Korean Peninsula issues. Preventing a Northeast Asia split into a southern U.S.-Japan-South Korea triangle confronting a northern China-Russia-North Korea triangle aligns with China’s interests. Given its close economic and technological ties with South Korea and Japan, China opposes intensified bloc confrontation. China firmly opposes the emergence of more nuclear-armed states in its neighborhood. Some Chinese scholars assert that under no circumstances would China tacitly accept North Korea attaining de facto nuclear status akin to India or Pakistan. China’s dilemma lies in balancing its enforcement of UN sanctions—which has drawn North Korea’s ire—with calls for trilateral cooperation with Russia and North Korea to counter U.S. pressure. In May 2025, China’s Deputy UN Ambassador Geng Shuang stated that China has shouldered over 90% of the international burden and sacrifices in implementing UN sanctions on North Korea. Meanwhile, China must contend with U.S. "new Cold War" pressure, based on America’s own military deployments, U.S. bilateral military alliances, and America-led minilateral groupings like the Quad and AUKUS. China has sought to rebalance its diplomacy in recent years. For instance, it reaffirmed the goal of "denuclearization of the Korean Peninsula" in a trilateral leaders’ statement with Japan and South Korea in May 2022. This move was harshly criticized by North Korea. In addition, Beijing faces challenge in addressing its ties with South Korea. The increasing competitive economic relations between China and South Korea, negative shifts in South Korean perceptions of China, and former President Yoon’s linking of Taiwan and North Korean nuclear issues, further complicate bilateral coordination between Beijing and Seoul.

Third, South Korea’s role in mitigating the crisis warrants attention. Domestic political shifts in South Korea can significantly impact the peninsula’s future. Inter-Korean tensions actually mirror South Korea’s internal political divide. With the new presidency of Lee Jae Myung, South Korea may resume engagement with North Korea. During the election campaign, Lee pledged to restore inter-Korean military hotlines, halt provocations, and pursue mutually beneficial dialogue. However, amid deepening conservative-progressive polarization, his room for maneuver on the inter-Korean issue is quite limited. Even if Yoon Suk-yeol is impeached, conservative hardliners in South Korea will persist. The calls for South Korea’s independent nuclear armament or embracing NATO-style "nuclear sharing" are growing. In February 2025, South Korea Foreign Minister Cho Tae-yul urged the redeployment of U.S. tactical nuclear weapons and hinted at South Korea’s consideration on its nuclear arsenal. “It’s premature to talk about such a Plan B, but that doesn’t mean it’s off the table,” Cho said. “Given that international situations are developing in an unpredictable direction, this is a principled response that we must prepare for all possible scenarios.” In march 2025, The US Department of Energy designated South Korea as a “sensitive” country, which means South Korea became a proliferation risk. Those moves would influence the peninsula’s nuclear landscape.

Possible Pathways Ahead

The enduring Russia-Ukraine conflict as well as the newly erupted clash between Israel and Iran indicate the brutality of geopolitical rivalry in the current world. It is imperative to avoid a repeat of the tragic war on the Korean peninsula and in East Asia.

First, multi-dimensional dialogues should be revived to ensure political settlement and mitigate tensions. Denuclearization remains fraught, with the primary obstacle being U.S.-North Korea distrust. The two sides may consider to make phased, reciprocal agreements, such as a nuclear freeze in exchange for a peace declaration and sanctions relief. In addition, the inter-Korean dialogue needs to be encouraged, for rebuilding trust and prevent accidental clashes. It is essential to reestablish U.S.-China diplomatic and security channels and resume the consultations on the Korean peninsula issues. Improved governmental exchanges between China and South Korea can be useful in reducing misperceptions and miscalculations. Beijing has great expectations on the Lee administration to repair strained China-ROK relationship.

Second, to establish crisis prevention mechanisms is much needed given the increasing complexities of deterrence and the evolving nature of technology-driven warfare. In a highly tense military standoff, the possibility of armed conflict on the peninsula due to miscalculation is real. We need to address risks of military clashes, such as intercepting test missiles, attacking missile launchers, and waging cyberwarfare. The implications of integrating conventional and nuclear deterrence should be discussed in Track 2.0 and Track 1.5 dialogues. Feasible de-escalation measures should be identified. Some even argue that the initiatives to prevent nuclear safety and security crises need be developed. More importantly, it is counterproductive to connect the Korean Peninsula issues to the Taiwan question or the South China Sea disputes. We need to explore how to avoid vicious linkages between different security hotspots in the Asia-Pacific region.

Third, it is imperative to explore the pathways for building regional security complex based on mutual restraint. Regional security complex is a theory developed by Barry Buzan and Ole Wæver to highlight the security interdependence among relevant states. The essence of the Korean peninsula is a security issue, rooted in the persistent failure to establish a peace regime. It needs to explore the possibility of a four-party dialogue among the U.S., China, North Korea, and South Korea to sign a peace treaty. The security concerns of North Korea need to be taken seriously, and the gradual easing of sanctions against Pyongyang is still an important incentive for it to reconsider its nuclear ambition. However, US recent attacks on Iranian nuclear facilities may significantly impact North Korea’s calculations.

In the context of regional security complex, when developing military cooperation, the United States, South Korea, Japan and others should be attentive to the adverse impact of related initiatives on third parties and regional security. Some Chinese scholars discuss the possibility of a Northeast Asian security cooperation mechanism through the restart of the Six-Party Talks, and the necessity of exploring regional arms control consultations. In order to realize it, the trilateral cooperation among China, South Korea and Japan is critical, which can help avoid the bloc-like confrontation in Northeast Asia. ■

■ Minghao ZHAO is Professor and Deputy Director at the Center for American Studies at Fudan University.

■ Edited by Inhwan OH, Senior Research Fellow
    For inquiries: 02 2277 1683 (ext. 202) | ihoh@eai.or.kr