Late Tuesday night South Korean President Yoon Suk Yeol declared martial law, accusing the opposition party of “legislative dictatorship” and vowing to eradicate “pro-North Korean anti-state forces.” Almost as suddenly as martial law was declared, the legislature voted unanimously for it to end – sending the very military forces that attempted to lock down the National Assembly packing. What do Yoon’s actions mean for the future of South Korean politics? How might a collapse of South Korea’s conservative party affect U.S.-Korean relations? And what are the broader implications for American allies and partners in Asia?
Zack Cooper is a senior fellow at the American Enterprise Institute, where he studies US strategy in Asia, including alliance dynamics and U.S.-China competition. He also teaches at Princeton University and serves as chair of the board of the Open Technology Fund. Zack previously served as the assistant to the deputy national security adviser for combating terrorism at the National Security Council and as a special assistant to the principal deputy undersecretary of defense for policy at the Department of Defense. His upcoming book is Tides of Fortune: The Rise and Decline of Great Militaries (Yale University Press, 2025).