S. Korea capable of developing nuclear prototype within six months

President Yoon Suk Yeol's remarks on "the possibility of Seoul's possession of nuclear weapons" led to increased attention to the technological procedures and time period required for Korea to develop its own nuclear weapons. "South Korea already has the reprocessing and enrichment technologies at the level of nuclear states’," said Seo Kyun-ryul, an honorary professor of nuclear engineering at Seoul National University. "Once Korea decides to develop one, we can make a 20-kiloton prototype in just six months."

Plutonium can be created by reprocessing the spent fuel rods of around 20 nuclear plants in operation and Unit 1 of Wolseong Nuclear Power Plant, which was shut down in 2019. "Three shifts of 500 highly-skilled technicians a day will be enough to get six kilograms of plutonium within six months," said Mr. Seo. It means Korea can secure nuclear materials to the amount of three nuclear plants if it produces uranium by using laser-enrichment technology at the same time.

In 2000, the Korea Atomic Energy Research Institute successfully tested the production of weapons-grade uranium using laser-enrichment methods, which led to the International Atomic Energy Agency (IAEA)’s inspection. "A detonator can also be manufactured within a year,” a military source said. Experts say that a supercomputer simulation can verify the prototype without a nuclear test. Professor Seo predicted, "In two to three years after the completion of the prototype, we will be able to mass-produce tactical nuclear weapons that are miniaturized to 50 to 60 kilograms, and install them on fighter jets or Hyunmoo missiles."

However, it is widely believed that the option to be nuclear-armed is not feasible. If South Korea breaks the Nuclear Non-Proliferation Treaty (NPT) and starts nuclear development, the country will inevitably face unaffordable economic and diplomatic losses and damaged relations with the U.S. "South Korea‘s attempt to arm itself with nuclear weapons under the NPT system will take a huge toll on its economy caused by economic sanctions," said Park Won-gon, a professor of North Korean studies at Ewha Womans University.

"The government's principle to comply with the NPT system remains unchanged,” an official from the Presidential Office said on Thursday. “President Yoon's comments show his firm will at a time when North Korea is escalating its nuclear threat."


Sang-Ho Yun ysh1005@donga.com · Na-Ri Shin journari@donga.com