The Asan Institute for Policy Studies hosted the Asan Plenum 2026 on April 8, 2026 (Wednesday) at the Grand Hyatt Seoul under the theme “Modernizing Alliances.” The Plenum addressed key security challenges, including the evolving U.S.-led alliance system, the future of the Indo-Pacific security environment, expanding military, economic, and technological cooperation among allies, and responses to North Korea’s nuclear threat.

In his welcoming remarks, Dr. Chung Mong Joon emphasized that the U.S.-led alliance system has played a central role in winning the Cold War, shaping the modern international order, and contributing to South Korea’s economic growth and democratic development. He stressed, however, that alliances must continue to evolve and modernize in response to a changing security environment. In particular, he noted that shifts in U.S. strategy and deepening alignment among China, Russia, and North Korea have increased the urgency of alliance modernization.

Dr. Chung highlighted that South Korea represents one of the most successful cases of alliance cooperation, having achieved economic development and democratic consolidation based on the ROK-U.S. alliance. He emphasized that allies must continue to share the burden of collective security. At the same time, he called for reassessing the form of deterrence required as U.S. pressure grows for South Korea to assume ‘primary responsibility’ for defending the Korean Peninsula, given North Korea’s persistent nuclear threat.

In this context, Dr. Chung suggested that South Korea should consider holding accountable those countries that engage in opportunistic behavior by seeking benefits from both Koreas, proposing a “Korean version of the Hallstein Doctrine” as a possible policy approach.

He further proposed that alliance modernization should include ensuring allies’ nuclear sovereignty in deterrence and in responding to nuclear threats He emphasized the need for serious discussions on options once considered difficult, including the redeployment of U.S. tactical nuclear weapons to South Korea and nuclear sharing arrangements between Seoul and Washington. He also noted the importance of a coordinated approach involving both South Korea and Japan in addressing these issues.

In addition, Dr. Chung underscored the need to establish a collective security framework in the Indo-Pacific. He proposed the idea of an Asian version of NATO, tentatively referred to as an Indo-Pacific Treaty Organization (IPTO). He argued that the existing “hub-and-spokes” alliance system should evolve toward a “spoke-to-spoke” model that strengthens horizontal cooperation among U.S. allies, while also expanding cooperation with key partners such as India.

Dr. Chung concluded by emphasizing that alliance modernization must not lead to alliance weakening or termination. He stressed that strengthening nuclear deterrence through nuclear sharing and the possible redeployment of tactical nuclear weapons, along with building a regional collective security framework, will be essential to ensuring that the U.S.-led alliance system endures successfully for decades to come.

* Attachment: Full text of welcoming remarks by Dr. Chung Mong Joon