North Korea and South Korea are engaged in a high-stakes contest to build increasingly larger and more sophisticated missiles. This strategic arms race is driving regional tensions to new heights, with North Korea threatening the United States’ extended deterrence commitments to South Korea, while Seoul is openly considering strikes aimed at the very core of Pyongyang’s leadership.
Recent developments highlight how this arms race is evolving, as both Koreas push the boundaries of missile technology, provoking serious concerns about regional security and stability. The contest is intensifying amid growing uncertainties about the future of the US-South Korea alliance, especially as global political dynamics shift.
In late 2023, North Korea showcased a new missile system that captured global attention. According to a report from 38North, a photo was released showing North Korean Supreme Leader Kim Jong Un standing beside a newly designed road-mobile missile launcher chassis. The new chassis, featuring at least 12 axles, is a significant upgrade from the previous 11-axle Transporter-Erector Launcher (TEL) used for the Hwasong-17 intercontinental ballistic missile (ICBM).
This latest development signals North Korea’s ongoing commitment to enhancing its road-mobile missile deployment capabilities. Although 38North could not confirm the specific function of the new chassis, it speculates that the new TEL could be tied to a longer-range ICBM or even a space-launch vehicle (SLV). The TEL’s design and military paintwork strongly suggest its purpose is for deploying a more advanced ballistic missile.
The implications of this new system are profound. If the new TEL is intended for a follow-up design to the Hwasong-18 ICBM, it could enable North Korea to launch a larger payload, potentially including multiple warheads or decoys to enhance the missile’s range and effectiveness. The Hwasong-18, with its solid-propellant engine, has already raised concerns due to its enhanced concealment, ease of operation, and reduced need for support vehicles, all of which improve its survivability on the battlefield.
With a potential range of up to 15,000 kilometers, the Hwasong-18 could theoretically strike anywhere within the continental United States, depending on the payload. This capability underscores North Korea’s strategy to undermine the US-South Korea alliance by casting doubt on the United States’ extended deterrence guarantees, which aim to protect South Korea under the US nuclear umbrella.
By making the prospect of a North Korean strike on the US mainland more credible, Pyongyang may be attempting to erode the strategic logic that underpins US-South Korean defense commitments. This could force Seoul to rethink its military posture or even push for concessions, such as a reduced US military presence in the region or the lifting of sanctions.
South Korea’s Response: Hyunmoo-5 and the “Decapitation Strategy”
Not willing to be overshadowed by North Korea’s missile developments, South Korea has responded in kind. In early October 2024, during the country’s Armed Forces Day celebration, South Korea unveiled its largest ballistic missile to date – the Hyunmoo-5. The event, held at Seoul Air Base, was attended by President Yoon Suk Yeol and was seen as a direct message to North Korea that Seoul will not back down in this contest of missile supremacy.
According to Yonhap News Agency, the Hyunmoo-5 is a game-changer for South Korea’s strategic capabilities. The missile boasts a massive 8-ton warhead and can travel at ten times the speed of sound with a range of up to 3,000 kilometers. This gives South Korea the ability to strike targets deep within North Korean territory, including hardened underground facilities, which are often used by Pyongyang to shelter its military assets and leadership.
Military analysts suggest that the Hyunmoo-5 is part of a broader South Korean effort to neutralize North Korea’s asymmetric advantage in nuclear weapons. As Konrad Ruminski noted in a November 2023 brief from the Asia Research Center, the Hyunmoo-5 has been designed to carry the largest conventional warheads in the world, capable of creating seismic tremors strong enough to collapse underground structures buried up to 100 meters below ground.
Ruminski points out that this capability is central to South Korea’s “decapitation strategy,” a controversial military doctrine that involves preemptive strikes aimed at eliminating North Korea’s leadership, including Kim Jong Un. The logic behind the strategy is that North Korea’s leadership would be less willing to engage in military aggression if it faced a credible threat of being personally targeted in the event of a conflict.
The Hyunmoo-5, along with other advanced missile systems, could serve as the lynchpin of South Korea’s response to an existential threat from the North. However, Ruminski also notes that despite these advances, South Korea remains at a disadvantage in terms of strategic deterrence because it lacks its own nuclear weapons. While the Hyunmoo-5 may be capable of inflicting catastrophic damage on North Korean military facilities, Pyongyang’s nuclear arsenal gives it the ultimate upper hand in terms of deterrence.
PISU Strategy: Seoul’s New Offensive Posture
South Korea’s increasingly aggressive stance against the North is reflected in its new military doctrine, known as PISU: Punish Immediately, Strongly, and Until the End. As detailed by Sungmin Cho in a February 2024 article for the Center for Strategic and International Studies (CSIS), this strategy emphasizes automatic, personalized retaliation in response to any North Korean aggression.
The PISU strategy represents a significant shift in Seoul’s military thinking. Whereas South Korea has historically focused on deterrence and defense, PISU underscores a more offensive approach, signaling that Seoul is prepared to retaliate swiftly and decisively against any provocation from the North. Cho notes that this policy’s automaticity is designed to dissuade North Korea from testing Seoul’s resolve, as it signals a clear and unambiguous threat of military retaliation.
By emphasizing personalization, the PISU strategy also mirrors South Korea’s decapitation strategy, sending a direct message to Kim Jong Un and his inner circle that they would be personally targeted in the event of a conflict. This reflects South Korea’s growing concern that North Korea’s nuclear capabilities may embolden Pyongyang to act more aggressively, requiring a more robust deterrent to keep the peace.
US-South Korea Alliance at a Crossroads
The escalating missile rivalry between North and South Korea is unfolding at a time of growing uncertainty about the future of the US-South Korea alliance. With the 2024 US presidential elections looming, both Koreas are likely watching closely to see how the outcome will affect Washington’s commitment to the region.
Historically, the US-South Korea alliance has been a cornerstone of American foreign policy in East Asia. However, as Darcie Draudt-Vejares highlights in a recent analysis, the alliance has often been a topic of debate during US presidential campaigns. Under former President Donald Trump, the alliance was redefined in more transactional terms, with Trump demanding greater financial contributions from South Korea in exchange for continued US military support.
In contrast, Vice President Kamala Harris has emphasized the importance of maintaining strong alliances in the Asia-Pacific region as a counterbalance to China’s growing influence. Draudt-Vejares notes that Harris’s approach aligns with the strategic framework pursued by the Obama and Biden administrations, which prioritized multilateral cooperation and institutionalized alliances.
As the US heads into its next presidential election, South Korea is likely concerned about the potential for a return to the more transactional approach championed by Trump. Should South Korea perceive a weakening of US commitment to their alliance, it may feel compelled to take more aggressive unilateral actions to secure its defense, including bolstering its missile capabilities or even pursuing nuclear latency – the capability to develop a nuclear weapon on short notice.
The intensifying missile rivalry between North and South Korea is not merely a technological contest but a complex strategic battle with far-reaching implications for regional and global security. North Korea’s continued advancements in missile technology, coupled with its growing nuclear arsenal, present a direct challenge to the United States’ extended deterrence guarantees in East Asia. At the same time, South Korea’s development of the Hyunmoo-5 and its increasingly aggressive military posture underscore its determination to counter the North’s threats.
The outcome of this contest will hinge on several factors, including the future of the US-South Korea alliance and broader geopolitical shifts in the Asia-Pacific region. With both Koreas upping the ante, the risk of miscalculation or escalation grows ever higher. Whether the region can avoid a catastrophic conflict will depend on the ability of all parties involved to navigate this dangerous test of nerves.