Understanding the ‘I’ in denuclearization: Lessons from North Korea and Iran

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Understanding the ‘I’ in denuclearization: Lessons from North Korea and Iran

Published: 01 Jul. 2025, 00:03

Audio report: written by reporters, read by AI

Yoo Jee-hye

The author is the head of the diplomatic and security news department at the JoongAng Ilbo.

Since the administration of former President Moon Jae-in, the phrase “complete denuclearization” has often been used in reference to North Korea. However, the longstanding international standard in denuclearization efforts remains “complete, verifiable and irreversible denuclearization,” or CVID.

The shift in terminology during the Moon government was not incidental. Ahead of the April 27, 2018, inter-Korean summit at Panmunjom, North Korea expressed strong opposition to CVID. In response, the two Koreas agreed on a softer expression: “The South and the North confirmed the common goal of realizing a nuclear-free Korean Peninsula through complete denuclearization.”

The Moon administration maintained that “complete denuclearization” was essentially equivalent to CVID. While the interpretation is not incorrect in principle, it glosses over critical differences.

Smoke rises from a fire as the Israel-Iran air war continues in Tehran in this still image obtained from a social media video posted on June 17. [REUTERS/YONHAP]

In the CVID framework, the “C” or completeness of denuclearization is an end state — achievable only through the successful implementation of the “V” — verification — and “I” — irreversibility — components. In that sense, the Moon administration’s framing may have aligned with the broader goal, but it understated the significance of verification and irreversibility, which have proven the most difficult in practice.

Indeed, it is the “V” that has repeatedly stalled negotiations with Pyongyang. Verification exists for the sole purpose of confirming whether irreversible dismantlement — “I” — has truly been achieved.

At the Panmunjom summit, North Korean leader Kim Jong-un personally promised to dismantle the Punggye-ri nuclear test site. The following month, in May 2018, North Korea invited foreign journalists, including South Korean media, to witness what was billed as the test site’s demolition. Yet no outside experts were permitted to conduct inspections.

Seven years later, the third tunnel at Punggye-ri — one of the tunnels supposedly destroyed — has reportedly been fully restored and is capable of supporting a new nuclear test. This is the official assessment of intelligence authorities in Seoul and Washington.

This May 23, 2018, satellite image provided by DigitalGlobe shows the nuclear test site in Punggye-ri, North Korea. A group of foreign journalists went to watch the dismantling of the nuclear test site after eight reporters from South Korea received last-minute permission to join them. [AP/YONHAP]

The Punggye-ri case offers a textbook example of how difficult irreversibility can be. No follow-up verification was conducted, and the dismantling proved neither permanent nor disabling.

At the heart of true irreversibility in North Korea is not just the destruction of facilities but the scientists who built the program — the so-called “nuclear brains.” Despite international sanctions and limited resources, these scientists enabled Pyongyang to develop multiple nuclear warheads.

Experts note that “irreversible” does not mean nuclear rearmament is technically impossible. Rather, the goal is to raise the cost of reconstitution so high — in terms of time, resources and expertise — that the state is effectively deterred from pursuing it again. Even if infrastructure is destroyed, as long as the key scientists remain, the potential for nuclear revival remains significantly intact.

This image shows foreign journalists and North Korean internet connection staff at the Kalma Hotel in Wonsan, North Korea, on Tuesday, May 22, 2018. A small group of foreign journalists was in North Korea to cover the dismantling of the country's nuclear test site later this week, but without South Korean media initially also scheduled to participate. Pyongyang is allowing limited access to the site to publicize its promise to halt underground tests and launches of intercontinental ballistic missiles. It unilaterally announced the moratorium ahead of a summit between leader Kim Jong Un and U.S. President Donald Trump in Singapore on June 12. [AP/YONHAP]

This concept of irreversibility has resurfaced in light of recent developments in the Middle East. While attention has focused on Israeli airstrikes in Iran, reports suggest Israel’s primary objective was the assassination of Iranian nuclear scientists.

According to international media, Israel launched what was dubbed “Operation Narnia,” a coordinated effort to eliminate nine top Iranian nuclear scientists almost simultaneously in their homes in Tehran.

This action followed assessments that Iran had already enriched uranium to weapons-grade levels. With that threshold crossed, Israel opted to target the individuals behind the nuclear know-how. Shortly afterward, U.S. President Donald Trump ordered strikes on three Iranian nuclear facilities.

Debate continues over how much these strikes set back Iran’s nuclear capabilities. But the joint elimination of scientific personnel and physical infrastructure marked a rare realization of what might be called “physical irreversibility.”

For North Korean leader Kim Jong-un, these events may serve as a chilling warning. With little to expect from Trump diplomatically, Kim may be prompted to conceal his scientists even more thoroughly, strengthen ties with China and Russia and further accelerate the regime’s nuclear capabilities.

Although the Iranian and North Korean situations differ, the implications are likely not lost on Pyongyang. The recent U.S.-Israeli response to Iran represents an existential threat to any regime banking on nuclear deterrence. Trump has reiterated that any renewed uranium enrichment by Tehran will be met with further strikes.

Yet, physical elimination is not the only path to irreversibility. After the collapse of the Soviet Union, countries like Kazakhstan and Ukraine found themselves with nuclear weapons on their territory. The United States responded by enacting the Nunn-Lugar Act, which provided technical and financial support for nuclear dismantlement.

U.S. President Donald Trump, right, and North Korean leader Kim Jong-un shake hands during an encounter at the Panmunjom truce village along the inter-Korean border. [RODONG SHINMUN]

More importantly, the United States created programs to re-employ former Soviet nuclear scientists, offering vocational training and redirecting expertise away from weapons development. This approach aimed not to destroy knowledge but to change the environment and mindset in which nuclear arms were considered necessary.

There are, in short, multiple routes to achieving “I.” The path does not always have to run through missile strikes or tunnel demolitions. Creating the conditions under which nuclear weapons are no longer needed — or even desirable — is also a viable strategy.

That is a challenge Kim Jong-un may not be ready to confront today. But sooner or later, he will have to.

Translated from the JoongAng Ilbo using generative AI and edited by Korea JoongAng Daily staff.