South Korea’s Path to Nuclear Submarines

South Korea’s Path to Nuclear Submarines

Seoul can equip itself with this necessary capability without harming its U.S. relationship or international treaty obligations.


Also, actual nuclearization requires either plutonium or weapon-grade uranium to produce nuclear arms, but nuclear-powered submarines only need low-enriched uranium for propulsion. If the Korean government has a strong will, it can adjust uranium enrichment without violating the NPT by urging the White House to modify the ROK-U.S. nuclear agreement.

South Korea may legally use the IAEA’s safeguard agreement, INFCIRC/153, which enforces signatories not to convert sensitive nuclear materials into nuclear weapons. This indicates that Seoul will observe the core principle of peaceful use of atomic energy if it adopts only nuclear power for its submarines. INFCIRC/254 also enables signed states to transfer atomic enrichment technology to a third country only for a peaceful purpose. South Korea should use these legal rights for SSN development under the NPT framework. After London and Washington announced to provide SSNs to Canberra during the AUKUS meeting in 2021, the IAEA clarified that transferring nuclear-powered submarines without nuclear warheads does not violate the NPT. The IAEA’s stance practically opened the door for the future development of South Korean nuclear-powered submarines.


In short, South Korea must strive to gain support for nuclear-powered submarines from the United States. Seoul must establish a government-led task force and consider improving the current infrastructure for building SSNs through foreign cooperation and localization to shorten lead time development, given the volatile Asian security environment and opponents’ threatening military build-ups against Seoul.

Yulgok Kim is the Secretary General of the ROK Forum for Nuclear Strategy (ROKFNS). He tweets at @rokfns.

Image: Shutterstock.