[Opinion] The South China Sea: What South Korea Can Do Together with ASEAN

An impressive scene unfolded at the Seoul Defense Dialogue held on the 8th. A note was handed to Philippine Defense Secretary Gilberto Teodoro as he was speaking during a plenary session. It said that the South China Sea arbitration ruling was illegal and invalid. Teodoro appeared to identify China as the source of the note. He responded that China’s refusal to recognize the ruling stemmed from the fact that it had lost the case. He further pointed out that China was trampling on the United Nations Convention on the Law of the Sea (UNCLOS) and showing disrespect to host country South Korea. It may have looked like a minor disturbance, but the scene captured the reality of the South China Sea: a power struggle over international law and a China with no intention of backing down.
The South China Sea is a major route for South Korea’s import and export cargo and energy supplies. The crisis in the Strait of Hormuz, which has continued since late February, showed that freedom of navigation has also become an issue requiring costs and burden-sharing. Against this backdrop, stability in the South China Sea is more urgent than ever.
This year, the Philippines assumed the ASEAN chairmanship. It has held monthly negotiations with China, aiming to finalize within the year the South China Sea Code of Conduct (COC), which has been under discussion for more than two decades since 2002. The outlook, however, is not promising. Key issues—including whether the agreement will be legally binding, its scope of application, and the definition of “self-restraint”—remain unresolved. Differences between China and the Philippines persist, while ASEAN members also show a wide gap in priorities between claimant states such as the Philippines and Vietnam and nonclaimant countries. Reaching an agreement within the year appears difficult.
Yet other voices have emerged within ASEAN. Some argue that it is more important in practical terms to persuade China not to act more aggressively in the South China Sea and to ease tensions than to adopt the COC itself. The COC was not originally designed to resolve territorial disputes or demarcate maritime boundaries. Rather, it is a mechanism for managing clashes by establishing rules of conduct at sea. From this perspective, success should not be measured by whether negotiations conclude, but by the ability to reduce accidental clashes and genuinely stabilize navigation.
This is precisely where South Korea can contribute: helping ASEAN build its own capacity to manage its waters. Areas such as maritime domain awareness using satellite and vessel information, maritime traffic management, strengthening coast guard capabilities, search and rescue, and combating illegal fishing can ease tensions and support order without targeting any particular country. South Korea has much to offer in such nonmilitary cooperation, given its world-class shipbuilding and maritime technologies and its well-trained coast guard. ASEAN is also preparing to establish a coast guard forum and an ASEAN maritime center proposed by the Philippines.
The ASEAN-Republic of Korea Summit to be held in Manila this November could serve as a starting point. South Korea could take the initiative by proposing cooperation projects that would substantially enhance ASEAN’s maritime-management capabilities, such as building a joint maritime-domain-awareness platform and conducting joint coast guard training and capacity-building programs. This approach would not involve taking the side of any one great power. Instead, it would contribute to regional stability by strengthening ASEAN’s own capabilities. Through such efforts, South Korea could expand its standing in ASEAN as a reliable strategic partner, beyond being merely a cultural and economic partner.
As the verbal exchange in Seoul demonstrated, the order in the South China Sea is already an issue at our doorstep. That sea is not someone else’s domain for us to watch from afar as great powers compete. It is where our lifelines pass, and a shared challenge that we must manage together with ASEAN.