The Future of Nuclear Weapons in South Korea

Since the 1970s, South Korea has been a signatory of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). It officially became a denuclearized country after the United States removed all its nuclear weapons in 1991. 

Under the international treaty, South Korea and other member states are prohibited from creating nuclear weapons, in order to promote cooperation in nuclear energy and further the goal of total disarmament.

South Korea also signed another joint declaration with North Korea, a denuclearization and unification effort of the Korean Peninsula that agreed to not “test, manufacture, produce, receive, possess, store, deploy, or use nuclear weapons” that went into effect in 1992. Further clauses mandate nuclear energy use solely for peaceful purposes, and regular inspections to ensure compliance with the declaration.

Unfortunately, North Korea has repeatedly violated this declaration by launching six separate nuclear tests since 2006, not including the over 70 ballistic and cruise missile tests the country launched in 2022 alone. The most recent concerning behavior from North Korea came at the end of last year, when five North Korean drones crossed into South Korea, one of which breached the presidential office’s no-fly zone. 

The election of South Korean President Yoon Suk-Yeol in May , whose conservative policies take a harsher stance on North Korean dictator Kim Jong-Un’s regime than his deescalation-seeking predecessor, has contributed to this increase in tensions. 

In a meeting of Kim’s Workers’ Party at the end of last year, he cited Yoon’s government as a valid reason to center its nuclear policy on “a mass production of tactical nuclear weapons” and “an exponential increase of the country’s nuclear arsenal,” specifically as a defense mechanism against South Korea. 

All this comes in conjunction with Kim’s need to maintain his credibility after international sanctions, the COVID-19 pandemic and recent floods that devastated the economy. Peace talks on the Korean Peninsula now look less than promising.

While the country’s current policy under Yoon is to defend itself from North Korea by strengthening its alliance with the United States, the president stated during a recent policy briefing that South Korea would consider building its own arsenal should the North continue its escalations. 

Washington’s official policy maintains its goal of entirely clearing the Korean Peninsula of nuclear weapons, fearful of triggering an arms race should South Korea decide to do so.

The threat of nuclear war has garnered support among South Korean citizens for their government to build an independent arsenal. A joint survey published by the Carnegie Endowment for International Peace, the Chicago Council on Global Affairs and the Lester Crown Center on US Foreign Policy found that 71% were in favor of South Korea developing its own nuclear weapons, and 56 percent would support a deployment of U..S nuclear weapons into the country.

However, an independent arsenal is greatly preferred, as trust that the United States will defend South Korea against the North remains at only 61% despite repeated assurances from Washington and the 28,500 American troops still stationed in the country.

Opinions of analysts and policy makers are split. Some hold faith in the umbrella of protection that the United States provides, while others not so much. 

According to Sejong Institute senior analyst Cheong Seong-Chang, the United StatesU.S. would be safer if South Korea had nuclear independence. Washington would not have to sacrifice its own nuclear weapons to defend South Korea, and, as an added bonus, a nuclear arms race on the Korean Peninsula might encourage China to crack down on Kim, he says.

However, deciding to build its own arsenal would require South Korea to withdraw from the NPT, in which case it would be the only country to do so after North Korea did in 2003.

Article X of the NPT does allow for a member state to withdraw, provided it gives the UN Security Council three months’ notice and sufficient reasons. The reasons cited for withdrawal must be in the case that “extraordinary events, related to the subject matter of this [t]reaty, have jeopardized the supreme interests of its country.” The increasing threats of nuclear attacks from North Korea could be a potential justification for South Korea to withdraw. 

Leaving the NPT remains a last resort for now. In the meantime, Yoon and his Defense Ministry plan to hold tabletop exercises with their allies to strategize and determine how well-equipped they are in the event of an attack. 

South Korea’s Defense Ministry has other deterrence strategies, as well. In 2017, after North Korea’s sixth nuclear test, South Korea established a “decapitation unit” under the Korea Massive Punishment and Retaliation initiative, which would conduct cross-border helicopter and plane raids into North Korea under the cover of night. The unit’s imposing name aims to strike fear of assassination into Kim Jong-Un.

Other South Korean arms build-up programs include Kill Chain, which would detect incoming missile attacks and launch preemptive strikes, and the Korea Air and Missile Defense program, which aims to intercept incoming missiles. 

The debate on nuclear policy comes at a time when Russia’s invasion of Ukraine has raised global concerns of nuclear war, and self-defense capabilities seem not only appealing but also necessary. 

South Korea must first confront several problems: How heavily can it rely on the United States for protection in the event of a Northern attack? Would an independent arsenal of nuclear weapons trigger an arms race? And, what is the best decision the government can make to ensure the prosperity and peace of its people? 

There may not be one right answer, but safety cannot be guaranteed while nuclear weapons are in the hands of any nation with malintent. 


Aiden Fullwood

Aiden Fullwood is a junior majoring in International Relations with minors in Korean Studies and Cultural Diplomacy from San Diego. Since March of 2021, Aiden has volunteered as an English tutor with Aurora NK, an organization dedicated to the education, legal support, and healthcare of North Korean refugees. She is especially interested in humanitarian and immigration issues across the globe, as well as U.S. relations with China and North Korea, and is eager to learn more through reporting on said topics with Glimpse. In the future, Aiden hopes to achieve fluency in Korean and Spanish and potentially work for the United Nations.