US ‘nuclear sensitive’ tag for South Korea stirs political blame game

The designation has put further strain on the East Asian nation’s already highly polarised political landscape

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Protesters stage a rally in Seoul calling for impeached South Korean president Yoon Suk-yeol to step down on Monday. Photo: AP

Published: 8:00am, 18 Mar 2025Updated: 8:03am, 18 Mar 2025

Washington’s move to designate South Korea as a nuclear “proliferation-sensitive” state has alarmed Seoul, with analysts linking the decision to domestic political turmoil and warning the classification could strain bilateral cooperation in critical sectors such as defence and technology.

South Korea was added to the US Department of Energy’s list of sensitive countries in January under then-president Joe Biden. On Friday, the department confirmed the designation but did not elaborate on why the decision was made.

The move followed a period of political instability in South Korea, including president Yoon Suk-yeol’s controversial martial-law decree on December 3, amid growing calls for Seoul to pursue its own nuclear weapons.

South Korea’s impeached president Yoon Suk-yeol arrives at his official residence after being released from detention on March 8. Photo: EPA-EFE

The designation has put further strain on the country’s already highly polarised political landscape. The liberal opposition party blamed the martial-law decree for stoking tensions, while Yoon’s ruling conservative People Power Party (PPP) accused the opposition of fuelling Washington’s mistrust with its perceived pro-China stance.

South Korean analysts say this fractious environment – combined with hardline rhetoric advocating nuclear development – may have prompted the new US classification.

“This move signals that South Korea will now be under US scrutiny due to concerns over proliferation risks, and this is deeply concerning,” Yun Jong-il, a professor of nuclear engineering at the Korea Advanced Institute of Science and Technology, told This Week in Asia.

“The geopolitical uncertainties, particularly in the wake of the martial-law decree, likely triggered alarm bells in Washington. South Korean politicians have also been openly discussing the possibility of developing nuclear weapons.”

The debate about nuclear armament in South Korea has been fuelled by growing military cooperation between Russia and North Korea amid the war in Ukraine, he said.