Seoul unveils nuclear submarine strategy amid regional undersea arms race

The South Korean government has formally announced the Jangbogo-N Project, a strategic initiative to develop nuclear-powered attack submarines, with the first vessel expected to be operational by the mid-2030s. Defence Minister Ahn Gyu-back unveiled the plan at a Future Defense Strategy Committee meeting at the naval base in Jinhae, describing it as a national strategic project that leverages South Korea’s existing shipbuilding and nuclear power technologies.

The initiative involves a decade-long construction period and a projected 30-year operational life for the vessels. According to the Defense Ministry, the submarines will possess dramatically enhanced operational capabilities compared to existing diesel-powered equivalents, playing a core role in responding to threats such as North Korea’s submarine-launched nuclear and missile capabilities.

Seoul is advancing the plan following endorsement from the United States, which has pledged assistance with propulsion systems for the conventionally armed vessels. However, logistical details remain under negotiation. During talks in October, US President Donald Trump indicated the submarines would be built in Philadelphia, but recent statements suggest the vessels will instead be constructed in South Korea.

Experts note the project serves broader strategic and industrial objectives. Choo Jae-woo, a professor of foreign policy at Kyung Hee University, stated the submarines are necessary to resist increasing incursions into territorial waters by China and to strengthen defenses in the East Sea. Additionally, the project is expected to expand South Korea’s nuclear industry, facilitating uranium enrichment and the development of technology to reprocess civilian nuclear waste.

The announcement underscores a deepening undersea arms race in Northeast Asia, with China, North Korea, and Japan all ramping up their respective capabilities. While some analysts question the immediate military necessity given the current state of North Korea’s fleet, others suggest the US approval may stem from hopes that South Korean submarines will serve as valuable assets in a potential crisis over the Taiwan Strait.