Flashpoints | Security | East Asia

Whether Kusong or Yongbyon, North Korea Will Never Give Up Its Nuclear Weapons Program

A controversy over the South Korean unification minister’s comments exposes the illusion at the heart of decades of North Korea policy.

In this file photo, provided on April 14, 2023, by KCNA, Kim Jong Un and his daughter observe the test-launch of the Hwasong-18 ICBM at an undisclosed location in North Korea.

A single sentence uttered in the National Assembly of South Korea has laid bare just how fragile the architecture of the South Korea-U.S. intelligence relationship can be, and how detached from reality the cornerstone of Washington’s North Korea policy has become.

On March 6, Unification Minister Chung Dong-young named Kusong, North Pyongan Province, as the location of a third uranium enrichment facility in North Korea. It was the first time a senior South Korean government official had publicly identified the city by name. Within weeks, Washington had restricted the sharing of satellite-derived North Korea intelligence with Seoul. Some observers in Seoul believe that Chung’s remarks were responsible – and could be affecting South Korea-U.S. defense cooperation more broadly.

The main opposition People Power Party called for Chung’s immediate dismissal, framing the incident as a catastrophic intelligence breach. On April 20, South Korean President Lee Jae-myung pushed back on X (formerly Twitter), arguing that the existence of a nuclear facility in Kusong had already been widely reported and that the characterization of Chung’s remarks as a leak of classified U.S. intelligence was flatly wrong.

The Unification Ministry has been explicit that Chung’s reference to Kusong drew not on classified briefings from U.S. or South Korean intelligence agencies, but on open-source material, including a 2016 report by the Institute for Science and International Security (ISIS) that identified a uranium enrichment-related facility near Panghyon Air Base. Chung himself stated that he had received no intelligence briefings on nuclear facilities since taking office. The Unification Ministry confirmed that no information related to Kusong was provided by any other agency.

Critically, Chung had made essentially the same remarks at his confirmation hearing in July 2025 without triggering any reaction from Washington. If the information was genuinely sensitive enough to warrant a cutoff of intelligence sharing, the threshold for that response was applied inconsistently and retroactively.

South Korean Defense Minister Ahn Gyu-back told lawmakers that no formal protest from U.S. Forces Korea Commander General Xavier Brunson had been delivered to his ministry. He also agreed that Chung’s remarks could not reasonably be characterized as a disclosure of classified material, given how widely the underlying information had already been published.

More to the point, South Korea does not rely solely on the United States for intelligence on North Korea. Its own National Intelligence Service, military surveillance assets, and a network of international intelligence-sharing partners provide independent streams of information. The assumption embedded in Washington’s response that any South Korean knowledge about Kusong must have originated from the U.S.-provided intelligence reflects either a misreading of Seoul’s independent capabilities or a deliberate effort to exert pressure for other reasons.

Long before Chung named Kusong, the U.S. itself had publicly acknowledged that North Korea’s nuclear infrastructure extended well beyond Yongbyon. At his press conference after the February 2019 Hanoi summit collapsed, U.S. President Donald Trump said North Korea had been surprised that the United States knew about an additional uranium enrichment site. 

The reason Trump walked away from Hanoi was precisely that North Korean leader Kim Jong Un’s offer – full dismantlement of the Yongbyon complex in exchange for broad sanctions relief – was insufficient. Yongbyon was not the whole program and the summit’s breakdown centered around a public disclosure that covert uranium enrichment sites existed and that the U.S. had them in its crosshairs. In that context, the notion that Chung’s reference to Kusong seven years later constitutes a damaging revelation of previously hidden information is difficult to sustain.

The Kusong episode is, in the end, a sideshow. The more consequential question it raises is the one neither Washington nor Seoul’s conservative bloc wants to answer directly: Is North Korean denuclearization actually achievable? The answer is clearly no.

Why Denuclearization Is Not Coming

Since the Hanoi breakdown, Kim Jong Un has been unambiguous: North Korea’s nuclear arsenal is no longer up for negotiation. In September 2022, Pyongyang passed a law codifying the conditions for nuclear weapons use, including potential first use, and declaring the country’s nuclear status “irreversible.” In September 2023, North Korea enshrined its nuclear force-building policy in the constitution itself, making nuclear possession the basic law of the state. In a speech to North Korea’s parliament in March 2026, Kim reaffirmed his intention to continue to consolidate his country’s nuclear deterrent........

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