South Korea’s martial law moment: constitutional crisis, and the regional order
South Korea’s Martial Law Moment: Constitutional Crisis, and THE regional Order
WRITTEN BY DR SEOHEE PARK
6 January 2025
South Korean President Yoon Suk Yeol’s declaration of martial law on 3 December 2024 emerged from mounting domestic challenges. By November, his approval ratings had plummeted to a historic low of 19 per cent, driven largely by controversies surrounding First Lady Kim Keon Hee, including allegations of stock manipulation, accepting luxury gifts, and interfering in party nominations. The situation was further complicated by internal conflicts within the ruling People Power Party (PPP) and Yoon’s deteriorating relationship with party leader Han Dong-hoon, who resigned on 16 December.
The hasty and unilateral nature of the declaration was evident in Cabinet testimonies. During the Cabinet Meeting, Finance Minister Choi Sang Mok (the acting president and acting prime minister since 27 December 2024) and Foreign Minister Cho Tae Yul were the strongest opponents, their resistance stemming from their understanding of South Korea’s economic and diplomatic vulnerabilities, particularly the nation’s dependence on stable exports, exchange rates, and international alliances. Choi received less than 30 minutes’ notice before the announcement. Despite his desperate attempts to prevent it, warning that it could “destroy all the achievements South Korea has built over the past 70 years”.
The declaration sparked immediate and fierce opposition, rooted in South Korea’s deeply embedded historical trauma. Citizens immediately gathered at the National Assembly building, their response driven by a collective memory of past authoritarian suppression. This reaction reflected how profoundly the Mencian principle that “the people are of supreme importance; the state comes next; last comes the ruler himself” had been violated in South Korea’s modern history. The nation’s experience with martial law, from Syngman Rhee’s anti-communist crackdowns in 1948, through Park Chung-hee’s military dictatorship (1961-1979), to Chun Doo-hwan’s violent suppression of the 1980 Gwangju Democracy Movement, has left deep scars on the national psyche.
The National Assembly’s response was swift and decisive. Despite police controlling access to the building and military personnel disrupting proceedings, lawmakers rushed to convene at the National Assembly building in Yeouido. The plenary session finally convened past midnight, resulting in a unanimous vote from all 190 present members, including 18 from the ruling PPP and 172 opposition lawmakers, demanding the withdrawal of martial law. This unified response demonstrated the strength of South Korea’s democracy, which was hard-won only in 1988 after decades of authoritarian rule.
This crisis represents more than a domestic Korean political drama; it tests the resilience of regional alliances and could accelerate broader geopolitical shifts in an increasingly complex Northeast Asian landscape.
The crisis has now moved to the Constitutional Court following the National Assembly’s 14 December impeachment motion against Yoon. The court faces unprecedented challenges, operating with just six justices instead of the mandated nine due to pending nominations. The National Assembly has reached a bipartisan agreement to nominate three justices, but tensions remain over the appointment process. The ruling PPP strongly opposed the nominations, arguing that it compromises legal impartiality, while the opposition Democratic Party (DP), controlling the special hearing committee, pushed to complete the nine-justice bench before the Court's first preparatory hearing on 27 December.
Regional implications and security partnerships
The timing of this constitutional crisis proves particularly challenging for regional stability. With Donald Trump’s return to the White House this month and Shigeru Ishiba's emergence as Japan's new prime minister in October 2024, Northeast Asia faces a period of significant diplomatic realignment.
The current situation has severely weakened South Korea’s diplomatic momentum, with Foreign Minister Cho acknowledging that “restoring it will take time”. The risk of diplomatic isolation or “Korea passing” is growing significantly. Trump’s first post-election press conference on 18 December highlighted his willingness to meet Japanese Prime Minister Ishiba and Chinese President Xi, while notably excluding South Korea from key diplomatic discussions. Such an omission marks a significant departure from earlier signals of cooperation, particularly regarding the shipbuilding industry, and indicates potentially diminishing US interests in maintaining balanced trilateral engagement in Northeast Asia.
The achievements of the recent Seoul-Tokyo rapprochement also now face potential reversal. Under the Yoon administration, bilateral relations witnessed remarkable improvement through the resolution of semiconductor trade restrictions and strengthened security cooperation via the Camp David summit. However, the probable succession of Lee Jae-myung, Yoon’s progressive rival, combined with the current constitutional crisis threatens to unravel these diplomatic gains. Lee has consistently maintained a hardliner stance towards Japan and criticised efforts for trilateral cooperation. His past criticisms of Yoon’s foreign policy direction and emphasis on historical disputes signal a return to the diplomatic approach seen during Moon Jae-in’s presidency when South Korea prioritised engagement with North Korea while relations with the United States and Japan deteriorated. Such a possibility raises concerns in Tokyo about whether the sustainability of recent diplomatic progress can be maintained. This situation becomes more complex given Trump’s “America First” approach to alliance management and Ishiba’s distinct vision for regional security architecture.
Ishiba’s approach to regional security presents both challenges and opportunities amid South Korea’s political turmoil. His proposed “Asian NATO” framework aims to counter China’s growing influence and North Korea’s provocations through enhanced trilateral cooperation. However, South Korea’s political instability undermines these plans. His comparison of “Ukraine today is Asia tomorrow” and emphasis on Taiwan’s security takes on new urgency when South Korea faces a potential leadership change to Lee. This domestic upheaval in South Korea, combined with existing regional scepticism towards Ishiba’s Asian NATO vision, particularly from ASEAN nations wary of choosing sides between the US and China, creates a complicated diplomatic challenge.
The prospect of Lee’s presidency, which could mirror the previous Moon administration’s more conciliatory approach towards North Korea and potentially more distant stance towards traditional allies, has prompted Tokyo to begin preliminary discussions about strengthening its security partnerships beyond the peninsula. While Ishiba aims to elevate the US-Japan alliance to the level of the US-UK relationship, Japan is simultaneously pursuing a multi-layered approach. Beyond the Quad framework (comprising the US, Japan, India, and Australia), Tokyo is expanding its security footprint through its Official Security Assistance (OSA) scheme, which has now identified the Philippines, Indonesia, Mongolia, and Djibouti as recipients for non-lethal military equipment such as radar systems to enhance maritime surveillance capabilities. Should South Korea under Lee’s leadership prioritise the inter-Korea relationship over trilateral cooperation, as Moon did, this could lead to Seoul’s diminishing influence in the regional security landscape, even as Japan strengthens its network of security partnerships amidst growing concerns about China’s influence.
Future scenarios and opportunities
South Korea’s potential leadership change to Lee might yield unexpected opportunities for regional cooperation. Trump’s demonstratable openness to North Korean diplomacy could align with Lee’s preference for engagement, following Moon’s footsteps. Meanwhile, Ishiba’s pragmatic stance on China, balancing security concerns with economic realities, suggests the potential for more flexible, issue-by-issue cooperation rather than rigid alliance structures. Areas of potential collaboration extend beyond North Korean denuclearisation efforts to practical economic partnership. These include maintaining semiconductor supply chains, developing joint disaster response capabilities and exploring shared approaches to emerging technologies, which are key priorities in Ishiba’s regional vision. Japan has also signalled interest in maintaining working-level diplomatic channels and people-to-people exchanges regardless of political changes.
The DP’s control of Seoul’s legislative agenda, demonstrated through the impeachment process and Constitutional Court appointments, signals their growing influence over policy direction. Their successful framing of the martial law declaration as a democratic crisis has resonated deeply with the public, suggesting lasting impacts on regional relations. The crisis has further escalated with the National Assembly’s unprecedented impeachment of Acting President Han Duck-soo (prime minister) on 28 December, following President Yoon’s impeachment. This crisis represents more than a domestic Korean political drama; it tests the resilience of regional alliances and could accelerate broader geopolitical shifts in an increasingly complex Northeast Asian landscape.
DISCLAIMER: All views expressed are those of the writer and do not necessarily represent that of the 9DASHLINE.com platform.
Author biography
Dr Seohee Park is a postdoctoral research fellow at Tohoku University and a lecturer at Ritsumeikan Asia Pacific University. Her research interests encompass geopolitics, geoeconomics international political economy, regional security dynamics in the Indo-Pacific, and the strategic implications of high-tech industries, including semiconductor supply chains. Image credit: Wikipedia/Daily Minjoo.