South Korea Moves Forward with Nuclear Submarine Program to Counter North Korea

South Korea’s Nuclear Submarine Development

South Korea has launched a project to build its own nuclear-powered attack submarines, which will operate on low-enriched uranium. Known as the Jang Bogo N program, this initiative is designed to bolster the country’s defense capabilities amid ongoing threats from North Korea. The first nuclear submarine is expected to be launched in the mid-2030s, with commissioning planned for the latter half of that decade or later. For context, this marks a significant shift in South Korea's naval strategy, as it currently relies on conventional diesel-electric submarines.

Defense Minister Ahn Gyu-bak emphasized that nuclear submarines will play a crucial role in countering North Korea’s nuclear and missile threats.

“Nuclear submarines are expected to play a key role in countering North Korea’s nuclear and missile threats due to their ability to remain submerged for extended periods and their high mobility,”

Technical Details and International Cooperation

The new submarines will use low-enriched uranium with enrichment levels of up to 20%. South Korea is bound by a bilateral agreement with the United States that prohibits the use of nuclear materials for military purposes. However, Washington has agreed to support Seoul’s development of nuclear attack submarines and pledged cooperation on nuclear fuel supply. Following this backing, South Korea decided to accelerate the project's timeline.

On May 26, 2023, North Korea launched several short-range ballistic missiles toward waters off its west coast. This was the North’s first known missile test since April, when it also fired short-range missiles and claimed to have used cluster munitions. South Korea’s push for nuclear submarines is a direct response to these provocations and reflects its determination to strengthen national defense. This development underscores the growing security competition in Northeast Asia, where regional powers are modernizing their militaries.

The construction of nuclear submarines represents a major step in enhancing South Korea’s defense posture against rising threats from the North. Beyond boosting Seoul’s military capabilities, the project highlights a new security reality in the region, where inter-state competition is intensifying. The partnership with the United States on nuclear fuel supply also reinforces the strategic alliance between the two countries, aimed at maintaining stability in Northeast Asia.

In light of recent developments, including North Korea's latest missile tests, South Korea's decision to advance its nuclear submarine program underscores the growing urgency to enhance its defense strategy against persistent threats from the North. This proactive approach reflects a significant shift in military preparedness in the region.