Seoul's nuclear gambit is not in favor of alliance politics

Mitch Shin

Jagannath Panda

By Mitch Shin and Jagannath Panda

South Korean President Yoon Suk-yeol has begun the New Year by provocatively underscoring his hawkish approach to North Korea, evident since his presidential campaign days. In early January, however, he may have overstepped his brief by suggesting that if the threats from North Korea grow, South Korea could consider developing nuclear weapons or asking the United States to redeploy nuclear weapons.

Notably, on careful consideration, the statement does not seem as off the cuff as it may appear at the outset. Primarily because it was made on the back of his assertions earlier the same month about the inadequacy of the U.S. extended deterrence and the need for joint nuclear exercises with the U.S. In response, the U.S. has rejected both Yoon's ideas, namely nuclear armament and joint nuclear exercises, by repeatedly emphasizing the complete denuclearization of the Korean Peninsula.

As a result, Yoon has in the aftermath of his global headline-generating remarks tried to calm the waters: In an interview with the Wall Street Journal at the World Economic Forum in Davos soon after, he reiterated his trust in the U.S. extended deterrence and his will to respect the Non-Proliferation Treaty (NPT) regime, which bars the parties to the NPT (including South Korea) from acquiring nuclear assets.

In the interim, many analyses listing the pros and cons of South Korea acquiring its own nuclear weapons have been published. For example, Seoul Mayor Oh Se-hoon of the ruling People Power Party (PPP) ― and a potential candidate for the next presidential election ― recently argued for the need for an "active nuclear umbrella," highlighting the conservatives' support for Yoon's bold proposition. In addition, Yoon might have even set the timetable for the country's nuclear development.

On the other hand, amid the unprecedented missile launches by North Korea last year, Washington has reassured its full commitment to defend Seoul from any nuclear attack. Regardless, some have favored the South's nuclear development overture, claiming that the U.S. might not use its nuclear weapons to defend the South in the event of an emergency on U.S. soil, that is, if North Korea attacks cities on the West Coast of the U.S. with its nuclear weapons.

In other words, the contention is that the U.S. would not be able to fully use its resources to protect the South when there is an increasing possibility of the North using its nuclear weapons directed at the U.S. mainland.

Further, this stress on a pro-nuclear armament initiative is reminiscent of the 1970s when the controversial Park Chung-hee government authorized a covert nuclear weapons program amid questions about the U.S. commitment to defend the South. Declassified intelligence documents years later revealed that these ambitions were discovered and thwarted due to strong U.S. opposition for fear of influencing the balance of power in Northeast Asia.

Pro-armament arguments remain the grounds for recent domestic opinion poll results declaring that more than half of South Koreans support the country developing nuclear weapons due to the growing threat from North Korea. At a time when the peninsula is under unprecedented nuclear threat, history too, therefore, evokes public support for South Korea strengthening its own nuclear capabilities.

Nonetheless, the U.S. and the international community will not support the South's designs to develop nuclear weapons. The reasons include fear of reprisals from the North and a detrimental change in the region's status quo. Moreover, as the complete denuclearization of the Korean Peninsula is the ultimate goal of the U.S., it will not consider redeploying its tactical nuclear weapons on the South's soil either.

At the same time, if South Korea persistently questions the execution capabilities of the U.S. extended deterrence, Washington may also rethink the necessity of spending enormous amounts of money and resources to defend South Korea: Under the Mutual Defense Treaty signed after the 1950-53 Korean War, about 28,500 troops are stationed in South Korea.

Such a narrative could be a bellwether for straining the relations and weakening the military alliance between the two countries ― which would bode well for North Korea's aim to weaken the South Korea-U.S. leverage in the region.

Besides, South Korea's nuclear development will also become a main catalyst for the North boosting up its nuclear capabilities further. It will also provide Pyongyang grounds to appeal to the international community against the unfairness of the economic sanctions on the North.

The main purpose of South Korea acquiring nuclear weapons is to deter North Korea's nuclear and missile threats. This rationale has been consolidated in the wake of Russia's invasion of Ukraine. However, it is too risky an endeavor, especially when there is plenty of room to closely coordinate with the U.S. and strengthen the country's military capabilities.

In addition, considering the status of the U.S. military assets, including its nuclear and conventional missile programs, South Korea does not need to develop its own nuclear weapons unless the U.S. withdraws its troops from its soil or the Mutual Defense Treaty is abrogated.

Ironically, the South Korean conservatives who prioritize the strengthening of the South Korea-U.S. military alliance are the ones vigorously supporting the domestic nuclear development rhetoric, which will surely weaken the alliance. While reiterating that the alliance with the U.S. is ironclad, they have jeopardized the U.S.-South Korea relations in jeopardy by adopting a one-dimensional formula: "nuclear to nuclear."

Taking the long view, rather than fan the controversial and boastful talk, Yoon must put his nuclear armament plans in perspective by developing a well-thought-out countermeasures strategy, including the prospects of a worst-case scenario. Public awareness about the nuclear-armament implications is also a relevant need to avoid misinformation chaos.

National security needs to be preserved. Importantly, however, to achieve its "global pivotal state" ambition, Seoul needs to be more responsible while advancing radical thoughts that could endanger its reputation, ties with the U.S., and the region's tenuous stability.

Mitch Shin is an assistant editor at The Diplomat and nonresident Korea Foundation fellow at Pacific Forum. Jagannath Panda is the head of Stockholm Centre for South Asian and Indo-Pacific Affairs at the Institute for Security and Development Policy, Sweden and a senior fellow at the Hague Centre for Strategic Studies (HCSS), the Netherlands.
The views expressed above are the authors' own and do not reflect the editorial direction of The Korea Times.