For decades, South Korea was an example of the United States’ unyielding stance on nuclear nonproliferation.
In the 1970s, the United States pressured South Korea, a steadfast ally with whom it shared nuclear technology, to give up a clandestine nuclear weapons program. Then, it barred the country from enriching its own reactor fuel. The restriction held firm even after Seoul joined a nonproliferation treaty, accepted rigorous safeguards, and built one of the world’s largest nuclear power industries. Nor did the policy waver as North Korea built a nuclear arsenal on the South’s doorstep.
Now, the Trump administration has shattered that standard. By striking a deal that could lead to Saudi Arabia enriching uranium on its own soil, Washington has prompted an inevitable question in Seoul: Why Saudi Arabia, and not us?
South Korea has long negotiated with the United States for enrichment rights. While its Foreign Ministry declined to comment directly on the U.S.–Saudi accord, it said on Thursday that it was closely monitoring “trends in U.S. foreign policy on the nuclear energy sector” for potential impacts on its own talks. While the deal raises expectations for progress in South Korea’s negotiations with Washington, it could also seed deep friction in the seven-decade-old alliance if Washington continues to ignore Seoul’s demands.
“It is clear that the Trump administration is willing to make major geopolitical bargains with less emphasis on international norms and institutions,” said Leif-Eric Easley, an international studies professor at Ewha Womans University in Seoul.
The contrast between Saudi Arabia and South Korea exposes a stark double standard in American nuclear policy. Washington appears to have paved the way for enrichment rights for Saudi Arabia for power plants it has yet to build, while denying them to South Korea, which already operates 26 reactors and plans to build more to meet surging energy demands for the A.I. revolution. It has exempted Saudi Arabia from intrusive inspections by the International Atomic Energy Agency, which South Korea has long submitted to to assure the international community that no technology is diverted to weapons projects.
Many in South Korea find this American concession especially jarring given the geopolitical risks. Crown Prince Mohammed bin Salman of Saudi Arabia has openly warned that his kingdom would build a bomb if Iran did. By contrast, South Korea’s president, Lee Jae Myung, has repeatedly promised that Seoul will not pursue nuclear weapons, choosing instead to rely on the U.S. security guarantees for deterrence as North Korea expands its nuclear arsenal.
“The danger of a breakout by Seoul is likely lower because of its continuous close coordination with Washington on extended deterrence,” Professor Easley said, adding that unlike in the Middle East, “major war on the Korean Peninsula has been deterred for decades.”
As South Korea was pressured to abandon its weapons program, it signed a treaty with the United States in 1972 that barred enrichment without American consent. Even during a 2015 revision of the agreement, Washington mandated that any enrichment require written bilateral agreement.
Consequently, South Korea imports all of its uranium fuel. Seoul now wants independent enrichment capabilities to secure its fuel supply chain. It also wants to recycle spent fuel to reduce waste storage volume — a massive political headache in a densely populated country with a vocal environmental movement.
The U.S.-Saudi deal will likely take center stage when South Korea and the United States resume talks to implement the comprehensive investment and security agreement struck by President Trump and Mr. Lee in November.
Back then, Washington appeared to address Seoul’s grievances by promising to support a “process that will lead to” civil enrichment of uranium and reprocessing of spent fuel by South Korea. He also approved South Korea’s plan to build nuclear-powered attack submarines, pledging American help to secure uranium fuel for the vessels.
However, the broad wording left critical details unresolved, including whether South Korea could operate enrichment or reprocessing facilities on its own soil and whether those facilities would also supply fuel for nuclear submarines.
Talks aimed at resolving such questions were sidetracked by a separate trade dispute, and working-level negotiations only resumed last month.
South Korea aims to launch its first domestic nuclear submarine within a decade, using low-enriched fuel to ease proliferation fears. But the pathway remains unclear.
In 2004, the I.A.E.A. investigated South Korean scientists for unauthorized enrichment experiments. Today, many in South Korea openly view uranium enrichment as a vital path to “nuclear latency” — the ability to rapidly develop weapons if Mr. Trump’s transactional diplomacy renders the U.S. security guarantee, known as the nuclear umbrella, unreliable.
Despite the South Korean government’s repeated denials of any intent to build atomic weapons, public and political backing for a sovereign nuclear deterrent has increased in recent years, while North Korea’s nuclear threats have escalated. In December, Pyongyang unveiled the hull of what it described as its first nuclear-powered strategic guided missile submarine.
