Months after South Korea’s President Yoon Suk-yeol’s declaration of martial law in early December 2024, the country is still rocked by the aftershocks of political turmoil and intensifying partisan division.
Even with last Friday’s announcement by the Seoul Central District Court to release Yoon from prison – likely mere days ahead of the Constitutional Court’s upcoming verdict on impeachment – the long-term risks of national political divides and entrenched partisanship are starker than ever.
Aftermath of Yoon’s Call for Martial Law
Last December, 11 days after South Korea’s legislature, the National Assembly, voted to lift martial law, legislators passed an impeachment vote of 204-85, suspending Yoon’s presidential power. It was not shocking to most, given the severity of Yoon’s sudden utilization of martial law in what was perceived by many as a draconian overreach of his presidential powers.
Next, in a rapid, unprecedented series of historical events, South Korea witnessed the transition of three heads of state in just three weeks. On December 27, the opposition-led legislative, headed by the Democratic Party (DP), voted along party lines with a simple majority of 192-0 to impeach then-acting president Prime Minister Han Duck-soo. As a result, South Korea’s Finance Minister Choi Sang-mok now holds the power of acting president. For the first time in South Korea’s democratic history, presidential authority resides beyond the traditional president-prime minister nexus.
The country is still feeling the effects of December’s “constitutional crisis,” even months later. Despite South Korea receiving international praise for upholding its democratic institutions and values, domestically the politic landscape paints a different picture: partisan tensions are on the rise within and outside the government. With the Constitutional Court’s verdict likely to be announced as soon as Friday – and snap presidential elections to follow should the impeachment hold – many are uneasy about the long-term impact on the future of South Korea’s domestic policy and international relations.
South Korea’s Rising Polarization
South Korea is facing increasing political polarization, marked by growing animosity between the ruling conservative People Power Party (PPP) and the opposition DP.
This divide intensified following Yoon’s narrow election victory in 2022 – Yoon won by less than a percentage point over DP candidate Lee Jae-myung. During the 2024 National Assembly elections, the PPP hope to gain majority control of the legislature. Instead, the party ceded seats to the opposition.
Since then, South Korea’s divided government experienced a growing impasse between Yoon’s PPP-driven policy agenda and the DP-led National Assembly. The ensuing government gridlock stifled domestic decision-making, hindering policymaking and effective governance.
A semi-parliamentary presidential government, South Korea’s political system features multiparty presidential and unicameral legislative elections – and to a limited extent post-election coalition-building within the legislative branch.
Effectively, however, domestic politics falls along a two-party political spectrum, delineated chiefly by the right-leaning PPP and left-leaning DP. Given the potential for divided government, consensus-building and bipartisan collaboration between the presidential and legislative branch is key for well-functioning governance.
Yoon’s declaration of martial law – an act not witnessed in South Korea for nearly 40 years – sparked domestic fear, frustration, and protests, inciting fierce and fraught political narratives across the nation. Building upon pre-existing tensions, political leadership and public opinion is now further divided.
Impeachment by Varied Means
After Yoon’s imposition of martial law, South Korea’s legislative, government, and law enforcement institutions alike sought differing, overlapping routes toward re-establishing constitutional order and laying the groundwork for presidential accountability.
As detailed by Article 65 of the South Korean Constitution, the National Assembly maintained the rights to pass a motion for presidential impeachment with supermajority (two-thirds) approval. Following the National Assembly’s successful motion to impeach Yoon on December 14, 2024, the Constitutional Court’s review to adjudicate the motion is underway.
In addition to the formal impeachment review, South Korea’s anti-corruption and law enforcement agencies moved forward under Article 84, which denotes that a seated president can only be charged with two crimes while in office: insurrection or treason. Interestingly, this dual-pronged strategy represents a new chapter in South Korea’s constitutional history.
In the past 20 years, South Korea has had two previous impeachment cases, that of former presidents Roh Moo-hyun and Park Geun-hye. Roh’s impeached was dismissed, while Park’s was upheld by the Constitutional Court. Neither leader, however, experienced simultaneous injunctions by law enforcement during their impeachment review periods. Prosecutors waited until the weeks after the court’s impeachment verdict to indict and later charge Park. However, today’s political situation tells a different story.
Yoon’s initial refusal to comply with questioning may have instigated stronger measures, driving a joint effort by the Corruption Investigation Office for High-Ranking Officials (CIO), the Defense Ministry, and the police to obtain a search and arrest warrant against Yoon. With Yoon’s detention in January, many in South Korea – mainly PPP-led voices – called for appropriate due course of law in the proceeding criminal and impeachment trials.
Amid the ongoing political crisis, enacting justice is important, but showing non-partial, effective judicial proceedings is also paramount. The implications of Yoon’s arrest, prior to the Constitutional Courts ruling, opened the doors to wide-spreading narratives of biased judicial procedures, weakening the legitimacy of South Korea’s legal impeachment procedures. Setting such a precedent would be highly risky in the nation’s rising partisan environment.
Risks and Implications of Hyper-Partisanship
Whether the Constitutional Court decides to dismiss or uphold impeachment, the political landscape in South Korea will likely remain partisan. As each side of the political spectrum leans into extreme narratives either pro- or anti-Yoon – as also seen during and after the 2016 Park Geun-hye impeachment – there is a risk of middle-ground policies and voices being left behind.
Under long-term political crises, rising partisan division could undermine citizens’ belief in fair, legitimate policymaking, ultimately, leading to the erosion of domestic faith in democracy. Clearly, South Korea’s democratic institutions remain strong, despite recent upheavals. The shift, however, toward extreme partisan views, coupled with an inability for inter-party compromise, runs the risk of further alienating middle-leaning political voices.
If Yoon’s impeachment is upheld, South Korea’s Constitution requires a snap presidential election to be held within 60 days. South Korea’s political division is likely to deepen as candidates rush to the campaign field, leveraging political narratives without regard for bipartisanship. In this hyper-partisan environment, the prospects for short- or long-term bipartisan cooperation appear increasingly bleak.
Furthermore, within such partisan environments, issues do not stay rooted in the domestic policy space but, rather, are likely to affect South Korea’s foreign relations as political divides take shape in foreign policy rollbacks and revisions. Sharp political division between parties can lead to political instability and poor policy enactment during administration transitions.
Prospects for South Korea-U.S. Relations
The outcome of the Constitutional Court impending decision is yet unknown. Should the presidential office face its next potential pendulum swing between political parties, there is a possibility for stark change in South Korea’s recent foreign policy stance toward regional and global affairs.
No matter which party holds office, a strong domestic consensus forms the basis for foreign policy cohesion. If South Korea seeks to strengthen its role on the global stage, domestic unity and political stability will be critical for policy effectiveness and international credibility.
Moreover, with the Trump administration’s repositioning of U.S. global and domestic interests, where exactly South Korea fits in U.S. strategic interests in the Indo-Pacific region remains a relative question mark. There are reasons for both confidence and apprehension. Either way, South Korea will need a strong, domestic foundation to move forward domestically and on the international stage.
Unfortunately, the current trajectory suggests continued partisan conflict is likely, potentially undermining national cohesion and governance in the years to come.