On April 26, North Korea’s Supreme Leader Kim Jong Un delivered a highly symbolic and strategic speech at the Nampo Shipyard, while presiding over the launch of a new 5,000-ton destroyer. While the occasion marked a milestone in North Korea’s naval modernization, his speech was far more than a celebration of shipbuilding progress. It provided candid insights into how Kim views the current security environment on the Korean Peninsula.
Kim views reinforcing South Korea-U.S. extended deterrence as a substantial threat to the regime’s survival. Therefore, he aims to augment North Korean nuclear and military capability in all domains: land, air, and especially sea. Understanding Kim’s perception and how he plans to respond is crucial for the future of South Korea-U.S. extended deterrence.
Kim Jong-un’s Threat Perception
Kim Jong Un portrayed the South Korea-U.S. alliance’s deterrence measures – including strategic asset deployments, joint military exercises, and Seoul’s deepening integration into U.S. nuclear planning and operations – as inherently aggressive rather than defensive. Describing the regional security environment as “extremely unstable, like unpredictable ocean weather,” Kim interpreted extended deterrence measures as active preparations for war, prompting North Korea’s enhancement of nuclear and military capabilities.
Kim condemned recent South Korea-U.S. military exercises involving nuclear scenarios, accusing the alliance of escalating tensions and preparing for a potential nuclear conflict. He perceives the introduction of the new wartime operational plan, OPLAN 5022 – which explicitly includes decapitation operations and conventional-nuclear integration – as concrete evidence of preparations for nuclear conflict. Framing these drills not as routine defensive exercises but as aggressive actions targeting North Korea, Kim described OPLAN 5022 as “the clearest expression of a will to wage war,” underscoring its nuclear strike components as indicative of hostile intent.
Kim also argued that the United States and its allies are deploying strategic assets with unprecedented frequency and scale, which he views as a direct threat that legitimizes North Korea’s nuclear arsenal. According to a North Korean state media article, Pyongyang sees such deployments not as deterrence but as preparations for a preemptive strike.
What kinds of South Korea-U.S. strategic assets make Kim concerned? North Korean media cited U.S. ICBM interception drills and the deployment of F-35s, F-16s, and B-1B bombers with stealth capability as evidence of a first-strike, warfighting strategy.
What Is Kim’s Deterrence Plan?
To strengthen its nuclear and military deterrence, Kim Jong Un asserted a multifaceted strategy based on a legal background reinforced by offensive capability and rapid responsiveness. In 2022, North Korea codified a new nuclear doctrine that lowers the threshold for nuclear use, authorizing preemptive strikes in response to fatal military attacks on the leadership or strategic assets – such as key infrastructure or military facilities – or in the event of a conventional war to take the initiative. Kim’s April 2025 speech showed that he remains resolute in upholding the new doctrine. He continues to modernize the military with an emphasis on greater strategic strike capability, signaling North Korea’s long-term commitment to enhancing its deterrence, which is the primary objective for its nuclear weapons.
At the core of North Korea’s nuclear framework is the development of a “super-powerful preemptive strike capability” with a stronger naval force, emphasizing that deterrence requires not just defensive readiness but the ability to launch swift and overwhelming preemptive attacks through any means (including nuclear). These efforts include the deployment of nuclear weapons across all domains – air, land, and especially sea – to ensure immediate retaliatory or preemptive action. By having a lower nuclear threshold with greater offensive capability, Kim aims to reinforce deterrence against the perceived threat from the South Korea-U.S. alliance.
Expanding Naval Capacity’s Role in North Korea’s Deterrence
Kim Jong Un pledged to deepen North Korea’s deterrent posture across air, land, and increasingly sea-based platforms, emphasizing the newly launched 5,000-ton multipurpose destroyer Choe Hyon as both a symbol of military self-reliance and a critical advancement in naval nuclear deterrence.
According to Kim, the vessel is outfitted with a range of advanced systems, including anti-air, anti-ship, anti-submarine, and anti-ballistic missile capabilities. It is also capable of launching hypersonic cruise missiles and tactical ballistic missiles designed to strike ground targets. This capability allows the North Korean navy to project force beyond maritime domains and engage in land warfare, representing a fundamental shift in operational doctrine. The destroyer thus extends the reach of North Korea’s military power and signals its use as a platform for deterrence and even preemptive strikes, possibly with nuclear-tipped missiles.
Additionally, North Korea’s pursuit of nuclear-powered submarines, described as the “second signal flare” of its naval deterrence strategy, would significantly enhance its ability to project strategic deterrence and conduct retaliatory strikes beyond the Korean Peninsula – a goal underscored by Kim during a submarine-launched cruise missile test in January 2024.
Kim asserted that North Korea’s naval advancements would “enhance its position in the realm of nuclear use,” echoing his earlier statement in August 2023 that nuclear armament was critical for naval modernization. That goal was exemplified by the development of the Choe Hyon destroyer and future nuclear-powered submarines, forming the backbone of North Korea’s evolving naval nuclear strategy.
However, these naval advancements underscore a deepening security dilemma on the Peninsula, as the perceived threats from both sides drive this cycle.
Security Dilemma on the Korean Peninsula
Ironically, Kim’s justification for building such capabilities is rooted in the very phenomenon that spurred the South Korea-U.S. alliance to reinforce extended deterrence: North Korea’s relentless advancement of its nuclear arsenal. This interplay illustrates a classic case of what international relations theorists call the security dilemma – where one state’s defensive measures are interpreted by its adversaries as offensive threats, prompting reactive countermeasures, an arms race, and tension. It is difficult for states to distinguish whether new military capabilities are intended for attack or defense. The ambiguity of systems like destroyers armed with land-attack missiles or submarines with strike potential feeds into such a dilemma.
The United States and its allies now face a North Korea with advancing strategic capabilities in every domain, considering Kim’s interest in building up these capabilities to mitigate perceived external threats. With the lessons from the Ukraine War alongside Russian support, North Korea’s military capability will likely grow and modernize in significant leaps. In response, the South Korea-U.S. alliance will continue cooperating to strengthen extended deterrence. However, without a clear channel of communication, the potential for miscalculation grows. The line between deterrence and provocation becomes dangerously thin.
This spiral risks triggering rapid escalation, especially if North Korea conducts another provocation toward South Korea aimed at domestic legitimization, which happened during Kim Jong Il and Kim Jong Un’s succession periods. An incident could trigger Seoul’s prompt response based on its three-axis deterrence strategy, which includes a preemptive strike and massive retaliation. In this environment, such clashes may set off a spiral of escalation under the shadow of nuclear brinkmanship.
What Should the South Korea-U.S. Alliance Do to Prevent a Crisis?
Preventing an unwanted crisis by maintaining deterrence requires more than military signaling – it demands a robust U.S. commitment as a basis, crisis management channels as a safeguard, and establishing a political environment and will to pursue dialogue.
First, the presence of U.S. Forces Korea (USFK) should remain strong under all circumstances to avoid a mistaken signal of U.S. disengagement. While some advocate for reducing USFK based on South Korea’s conventional military superiority, cost-benefit issues, and concerns over U.S. entrapment, the force’s role extends beyond troop numbers – it serves as a vital indicator of U.S. defense commitment, underpinning deterrence in the Indo-Pacific that prevents unwanted crisis. Using withdrawal as a bargaining tool in defense cost-sharing negotiations sends dangerous signals of weakening commitment, thereby eroding deterrence.
Should Washington consider reallocating regional forces for greater flexibility in the Indo-Pacific, any adjustments to USFK must be paired with clear, reinforcing measures to prevent misinterpretation. While agility may enhance strategic deterrence, it risks emboldening Pyongyang’s opportunistic provocations and unintended escalation if not backed by a visible commitment. A steadfast U.S. presence on the Korean Peninsula not only deters Pyongyang but also limits escalation risks and reduces the likelihood of a dual contingency – such as one involving opportunistic moves by China in the event of the Korean Peninsula crisis – thereby preserving peace and stability in the Indo-Pacific.
Second, the South Korea-U.S. alliance should establish a strategic communication channel with North Korea. In the nuclear domain, crisis management, such as establishing a military-to-military communication channel, is important to de-escalate a crisis before it becomes uncontrollable. This is especially necessary considering how quickly a crisis would escalate given the current situation on the peninsula. This possibility is realistically limited considering Pyongyang’s unwillingness to hold discussions with Washington and Seoul. However, re-establishing the line of communication should be carried through in case of future negotiations with Pyongyang.
Lastly, creating the political conditions and will to pursue dialogue is essential for breaking the vicious cycle of confrontation and bringing North Korea to the negotiation table. Although President Donald Trump has showed interest in engaging with Kim Jong Un, North Korea may remain disincentivized to negotiate with the United States due to its deepening strategic alignment with Russia amid the ongoing Russia-Ukraine war. The resolution of the war in Ukraine could help untangle these intertwined political dynamics by weakening the mutual benefits that Pyongyang and Moscow currently derive from their wartime cooperation.
North Korea receives a wide range of advantages from Russia, including military technology transfers, economic assistance, and energy support. In return, Russia benefits from North Korean provisions mostly on the battlefield, such as ammunition, manpower (troops and labor), and medical support. However, once the war concludes, Russia’s need for such support may diminish, reducing its incentive to maintain a close partnership with Pyongyang. This shift would create an opportunity for the United States and South Korea to drive a wedge between Russia and North Korea through coordinated diplomatic efforts.
Until then, the Korean Peninsula remains trapped in a dangerous cycle, where deterrence and provocation grow in tandem, and the risk of crisis escalation looms ever larger.