Key Takeaways:

- In an era of intensifying conflict, rising military spending, and eroding trust, arms control remains not an idealistic relic but a strategic tool for managing rivalry and preventing unintended escalation. 

- Distinguishing clearly between arms control, disarmament, non-proliferation, and counter-proliferation is essential, particularly as narrow, treaty-centric interpretations have obscured the broader stabilizing value of arms control as a process. 

- For South Korea, adapting to North Korea’s de facto nuclear status requires rethinking policy frameworks—shifting from exclusive reliance on non-proliferation toward a more integrated approach that includes arms control, disarmament dialogue, and active engagement in global disarmament forums.

Today’s global environment is mired with tensions. Armed conflicts are becoming increasingly frequent around the world, the use of force has become normalized, and even the long-standing ‘taboo’ regarding the use of nuclear weapons appears to be waning. Competition has intensified in domains traditionally considered conducive to cooperation, such as trade, while advancements in science and technology have also emerged as critical components of national security, adding yet another source of friction among states.

Under such circumstances, a global arms race seems almost inevitable. According to the Stockholm International Peace Research Institute’s (SIPRI) annual Trends in World Military Expenditure, 2023 report, worldwide military spending increased for the ninth consecutive year, reaching USD 2.4 trillion. Expenditures rose by 6.8 percent from the previous year—the sharpest increase since 2009—and amounted to 6.9 percent of total government budgets across all states.[1]

Given this, arms control may be perceived as an idealistic and unattainable policy objective. Indeed, calls for arms control often fall on deaf ears amidst growing skepticism toward existing agreements and institutional arrangements. The impending expiration of the U.S.–Russia New START Treaty in February 2026, along with heightened concerns that it may not be extended, starkly illustrates this trend. This is largely because the conditions that facilitate dialogue and negotiation, such as a level of trust among states and well-functioning international organizations, including the UN, have weakened considerably in recent years.

Yet, an argument can be made that arms control is perhaps most required precisely during such times of heightened tensions and lower barriers to the use of force. Historically, discussions and negotiations on arms control were most active in periods when the perceived risk of conflict was high, especially during the early periods of the Cold War when fears of a nuclear war were at their peak. In this sense, escalating tensions and intensifying arms races underscore the significance of arms control as a means of managing conflict and preventing unintended escalation or war.

Arms control carries particular relevance for the Korean Peninsula. North Korea’s conventional and strategic provocations, including its nuclear program, have made arms control simultaneously “the most urgent and yet the most difficult” diplomatic challenge for South Korea.[2] Recently, debates surrounding North Korea’s potential status as a nuclear-armed state and the possibility of U.S.–North Korea arms-reduction negotiations have further elevated the issue’s importance.[3]

Against this backdrop, it is essential to undertake a more systematic examination of the various concepts and policy tools—arms control, disarmament, non-proliferation, and counter-proliferation—and to develop coherent diplomatic and security strategies. Although these approaches share common goals in pursuing peace as well as minimizing wartime destruction, and although they each emphasize diplomatic engagement, their operational logics and practical mechanisms differ substantially. A more precise understanding of these distinctions will enable more effective and targeted policy options.

Schelling and Halperin, who laid the theoretical foundations for arms control in the early Cold War, defined it “to mean all the forms of military cooperation between potential enemies in the interest of reducing the likelihood of war, its scope and violence if it occurs, and the political and economic costs of being prepared for it.”[4] Although early discussions centered around this more comprehensive conceptualization, the meaning of arms control gradually narrowed as U.S.–Soviet negotiations produced formal treaty arrangements.[5] Schelling would later lament in the mid-1980s that arms control had “gone off the tracks” by focusing on numerical limits rather than the qualitative characteristics of weapons.[6]

Excessive focus on the narrow, treaty-based definition risks underrating the broader value of arms control and may contribute to expanding skepticism toward its feasibility. By contrast, a broader understanding of arms control as encompassing “all forms of military cooperation between potential adversaries” makes it possible to appreciate the value generated by the process itself. In this vein, it is important to note that the United States and the Soviet Union clarified their shared objective of preventing a nuclear holocaust, built mutual trust through reciprocal cooperative measures, and institutionalized mechanisms that shaped and stabilized their strategic rivalry during the Cold War—all of which highlight the enduring significance of arms control.[7]

Meanwhile, non-proliferation and counter-proliferation are closely related to arms control, particularly in their efforts to restrict the possession and spread of weapons of mass destruction (WMDs). This interconnectedness is most clearly reflected in the ‘grand bargain’ at the core of the Nuclear Non-Proliferation Treaty (NPT). Under the NPT, non-nuclear-weapon states commit not to pursue nuclear weapons in exchange for guaranteed access to nuclear technology for peaceful purposes. In return, nuclear-weapon states pledge to pursue nuclear disarmament in a gradual and systematic manner. The treaty thus institutionalizes an interdependent structure founded upon three pillars: disarmament, non-proliferation, and the peaceful use of nuclear energy.

However, this grand bargain has increasingly become contested and has begun to strain the non-proliferation regime. The central issue is the perceived ‘imbalance of obligations’ precipitated by the failure of nuclear-weapon states to fulfill the disarmament commitments enshrined in Article VI. Nuclear-weapon states counter by citing adverse security conditions, the presence of states attempting to violate non-proliferation norms, and the existential risks associated with unilateral disarmament as reasons to continue prioritizing non-proliferation. Yet the frustration of non-nuclear-weapon states became especially visible with the adoption of the Treaty on the Prohibition of Nuclear Weapons (TPNW) in 2021, further illustrating the complex and intertwined nature of arms control and non-proliferation.

As alluded to above, South Korea faces complicated challenges in articulating clear positions on arms control and disarmament. In short, although these policies may contribute to peace and stability on the Korean Peninsula, concerns persist that they could also weaken deterrence and undermine national defense. Furthermore, given the apparent failure to prevent a nuclear North Korea coupled with growing domestic support for independent nuclear armament, South Korea’s views on non-proliferation has become increasingly complex. These considerations lead to the following conclusions.

First, sustained attention must be devoted to analyzing the relationships between arms control, disarmament, non-proliferation, and counter-proliferation. Existing scholarship tends to examine each in isolation with relatively little analysis of how these concepts and policies relate to one another.

Second, the operational logics of arms control and disarmament should be included in discussions on the issue of North Korea’s denuclearization. Since the 1990s, non-proliferation, counter-proliferation, and freeze-based arms-control measures were the main tools. However, given North Korea’s declared completion of its nuclear arsenal and growing recognition both at home and abroad of North Korea’s status as a de facto nuclear-armed state, future policy may need to shift towards nuclear arms control and disarmament.

Third, research on the UN disarmament agenda should be sustained to explore ways for South Korea to engage with it more actively. Academic and policy discussions within South Korea remain disproportionately centered on the North Korean nuclear issue, whereas Seoul’s activities at the UN General Assembly 1^st Committee and the Conference on Disarmament (CD) receive substantially less attention. Beyond the North Korean issue, articulating long-term strategies for contributing to the UN’s disarmament agenda can be an additional way to strengthen South Korea’s role as a responsible middle power.

Lastly, efforts to enhance the public’s understanding of arms control, with particular focus on adjusting expectations, may contribute to future successes. The various benefits of arms control—its formal recognition of adversaries as equal counterparts, its provision of essential channels for communication during periods of heightened tension, and its capacity to prevent unintended or undesirable arms races—should be more widely emphasized. Most importantly, arms control should be emphasized not as an act of benevolence, but as a foreign-policy tool firmly grounded in strategic reasoning, and thus an essential instrument for managing peace and maximizing national interest.