South Korean nukes and "more may be better"

Waltz’s “The Spread of Nuclear Weapons: More May Be Better” has passed from academic to popular reading in South Korea. But is it relevant?

Kenneth Waltz’s “The Spread of Nuclear Weapons: More May Be Better” seems to have passed from academic to popular reading in South Korea. I saw an ajumma in the park reading it while her poodle panted beside her in a dog pram. It was so uniquely Korean, I wanted to take a picture (but being shy I went home and used AI).

Waltz’s work, after filling South Korean PhD theses and academic papers in the 1980s and 1990s, seems to have returned as popular reading as South Korea’s debates securing an independent nuclear weapons program. Around 60-70% of the public now support getting nuclear weapons.

Personally, I’ve always wondered why the “More may be better” paper was popular amongst so many South Korean strategic studies and IR professors. Particularly when these are the same professors who pushed for a “Korean School of IR” - a school of thought that took into consideration Korea’s unique circumstances as opposed to the European/US centered vision of mainstream IR.

Do Waltz’s arguments make any sense on the Korean Peninsula? I really don’t think they do.

Waltz's thesis is that the spread of nuclear weapons can actually lead to greater stability, not less, under certain conditions. He argues that nuclear deterrence—by virtue of the sheer destructiveness and mutual fear of retaliation—tends to moderate state behavior. Even bitter rivals, if rational and politically stable, are likely to become more cautious once both possess nuclear capabilities.

In Waltz’s view, nuclear weapons “dissuade states from going to war more reliably than conventional weapons,” and therefore more nuclear states may lead to a more peaceful international order, rather than a more dangerous one.

So, the argument is, North Korea’s attainment of nuclear weapons over the past two decades validated Waltz’s point about nuclear deterrence between adversaries. Since developing credible nuclear capabilities, North Korea has not initiated a large-scale military conflict, and South Korea has likewise refrained from serious military escalation. The extreme consequences of miscalculation are understood by both sides. Conventional skirmishes—such as the shelling of Yeonpyeong Island or the sinking of the Cheonan—have become rarer, and more limited, precisely because the costs of escalation are now nuclear.

However, as North Korea progresses in its nuclear program, the situation is becoming more complicated. North Korea’s capacity is growing and there is increasingly a degree of asymmetry in deterrence in the Korean Peninsula. South Korea does not possess its own nuclear weapons and relies on the extended deterrence promised by the United States.

Seoul’s security is tied to the belief that Washington would respond with nuclear force if Pyongyang used nuclear weapons against the South. This arrangement is increasingly under strain.

Waltz acknowledged that nuclear deterrence requires credible retaliatory capability. The credibility of U.S. extended deterrence is what stabilizes the Korean Peninsula—but that credibility is now being questioned.

As North Korea develops intercontinental ballistic missiles (ICBMs) that can reach the continental United States, the logic of extended deterrence begins to erode. Would Washington really risk Los Angeles or Chicago for Seoul?

This is the core dilemma: as North Korea’s capabilities grow, the risk that the U.S. would hesitate to retaliate grows too. This introduces instability into the deterrence relationship, because Pyongyang might gamble on the assumption that Washington is bluffing.

Reflecting this, Waltz’s work is used to argue that South Korea should acquire its own nuclear weapons. Waltz argued that nuclear parity—even between rivals—creates predictability. If South Korea had its own credible second-strike nuclear capability, it would not be dependent on uncertain U.S. resolve. The deterrent relationship would be direct and symmetrical. Both North and South would have a mutual, national-level stake in avoiding conflict.

Under Waltz’s view, the slow spread of nuclear weapons (as has been the case) is manageable and potentially even beneficial. Supporters argue that South Korea, with its stable government, strong institutions, and historically restrained strategic culture, fits the profile of a “responsible” nuclear actor in Waltz’s taxonomy. Thus, by Waltzian logic, more may indeed be better.

Waltz was good, but he never saw ajummas with poodles reading his work in the park. He probably didn’t even know what an ajumma was. He didn’t know Korea—nor do people who argue more may be better on the Korean Peninsula.

Waltz’s argument is theoretical and rooted in neorealism and the systemic logic of deterrence—it embeds a number of implicit cultural, political, and historical biases that reflect a Western-centric, particularly Euro-American Cold War experience. These assumptions don’t universally translate to the realities of Korea. This is why I thought South Korean professors of the “Korean School of IR” wouldn’t buy into it.

Waltz treats the U.S.–Soviet Cold War experience as the ideal model of nuclear stability. He’s focused on major power stability. He assumes a bipolar structure with high actor rationality, stable bureaucracies, clear command-and-control chains, long-term status quo orientation, and strong institutionalized diplomatic interaction. None of these apply on the Korean Peninsula.

First, the Korean Peninsula is not bipolar. Sure there’s North and South, but they’re definitely not the only actors pushing this barrel. The Korean Peninsula is at minimum hexagonal, involving China, Russia, Japan, the U.S., and both Koreas. This multipolarity increases risks of misperception, alliance entrapment, and arms races in ways that Waltz’s bipolar doesn’t take into consideration.

What’s more amongst these six states, there are some pretty strong influencers on actor behavior. Waltz underestimates the risk of “catalytic instability”—where third-party actors seek to exploit tensions. It is not unimaginable that a Chinese operation in Taiwan would require North Korea to tie down U.S. forces on the Korean Peninsula. Nuclear weapons could conceivably play a role.

Second, Waltz downplayed domestic political instability, and the risk of accidental or unauthorized use. South Korea’s political cycles, intense domestic polarization, and the potential for opportunistic use of nuclear weapons for political signaling during crisis scenarios cannot be ignored. South Korea, while nominally rational and bureaucratic, operates in a volatile democratic environment where public opinion, politics, and increasingly extreme ideology influence national security policy. And North Korea? It’s a black hole.

North Korea’s internal decision-making is opaque, personalized, and at times highly erratic (well, after last December, so is South Korea’s). Policy shifts, whether domestic or international, often appear sudden and unaccountable, with little indication of internal debate or competing voices. This secrecy fuels external speculation and makes strategic forecasting difficult.

When put together, this spells disaster for crisis management. Diplomatic communication is a critical pillar of nuclear deterrence, serving to clarify intentions, manage misperceptions, and establish credible red lines between adversaries. Unlike conventional military posturing, nuclear deterrence relies heavily on signaling—making threats believable while avoiding escalation.

Open or backchannel diplomacy provides avenues for reassurance, crisis de-escalation, and damage control in the face of misunderstandings or accidents. Without clear and consistent communication, even rational actors risk spiraling into unintended conflict, especially under conditions of time pressure or technological surprise.

Communication between North and South Korea is sporadic, highly politicized, and vulnerable to sudden breakdowns, often depending on the broader geopolitical climate. Formal channels, like the inter-Korean hotline, are frequently severed by Pyongyang to signal displeasure, while informal or backchannel efforts remain constrained by mutual suspicion. This fragile communication environment heightens the risk of miscalculation during crises.

Lastly, Waltz downplays identity politics, nationalism, and the symbolic power of nuclear weapons. In East Asia, these elements are critical. Nuclear weapons are not just strategic tools—they are deeply entangled with historical trauma, colonial memory, national pride and autonomy.

From my point of view, through interaction and life experience in South Korea, the biggest challenge is the absolute lack of a nuclear taboo.

The nuclear taboo when written about in IR textbooks uses a VERY Western-centric (arguably also Japanese) position. It holds that the nuclear taboo is a widely held norm that deems the use of nuclear weapons morally unacceptable. They argue that after knowledge regarding the devastation of Hiroshima and Nagasaki became better known, it has helped restrain states from using or even pursuing nuclear weapons. If you’re in a Western country or Japan, you’ve probably grown up with it in comics, music, on TV and in film.

The nuclear taboo hardly exists in South Korea. It doesn’t exist in North Korea. In both countries, nuclear weapons contributed to ending the Japanese occupation, are seen as increasing the global rank of a country, and are seen as national achievements. Does this mean they’re more likely to be used? Maybe, I don’t know.

In the end, Waltz’s clean, elegant theory—crafted in Cold War corridors and built on assumptions of rational actors and symmetrical power—collides with the unruly complexity of the Korean Peninsula. What looks like stability from a U.S.–Soviet lens falls apart when faced with multipolar dynamics, volatile democracies, opaque autocracies, and a striking absence of nuclear taboo.

The irony is that while Waltz's arguments were once the domain of elite South Korean academics, they now roll in dog prams beside panting poodles—distilled into a popular logic that sees nuclear weapons not as apocalyptic, but as aspirational. Yet for all its renewed appeal, Waltz’s framework is ill-fitted to this place.

South Korea isn’t a controlled experiment in deterrence theory—it’s a pressure cooker of shifting alliances, historical memory, political turbulence, and unpredictable escalation paths. "More may be better" might have worked on paper. On the Korean Peninsula, it’s less a theory and more of a gamble—but one that may well be taken.