Gi-Wook Shin

On December 3, 2024, South Korea’s President Yoon Suk-yeol declared martial law in a late night address. The move shocked the country and the world, setting in motion a political crisis that continues today. With the testimony of military officials revealing a broader plot to arrest opposition political figures, Yoon was impeached by the National Assembly. While the Constitutional Court case to consider his impeachment proceeds, the Corruption Investigation Office for High-ranking Officials (CIO) is investigating Yoon on charges of insurrection – along with treason, the only crime that a sitting president can be charged with. After using the Presidential Security Service to repulse one arrest attempt, Yoon was arrested on January 15. Yoon’s detention – and a later court ruling extending it – sparked angry protests from his supporters, some of whom attacked and vandalized the court building.

How did South Korea get here?

The Diplomat’s editor-in-chief, Shannon Tiezzi, interviewed Gi-Wook Shin, the William J. Perry Professor of Contemporary Korea in Sociology at Stanford University. The national reaction to Yoon’s martial law declaration “underscores how South Koreans’ hard-won democracy is not taken for granted,” Shin, an expert on social movements and democracy in South Korea, says.

“...This episode highlights both the fragility and resilience of Korea’s young democracy.”

How did South Korea’s history as a dictatorship – and past experiences of martial law – inform both Yoon’s decision to declare martial law and the public response?

South Korea’s painful history with dictatorship and martial law casts a long shadow over contemporary politics. I entered college in 1979, a year marked by the assassination of Park Chung-hee in late October and a period of intense political instability ensued under martial law. In fact, President Yoon Suk-yeol entered a college in the same year as me, and it is hard to understand how he could forget these shared experiences and decided to declare martial law.

When Yoon declared martial law last December, it triggered an immediate and decisive public backlash, driven by a collective memory of decades of struggle against autocratic regimes. This reaction underscores how South Koreans’ hard-won democracy is not taken for granted. Civic groups, citizens, and lawmakers mobilized swiftly, reversing the martial law decision within six hours and passing the motion to impeach Yoon 11 days later. Despite recent backsliding, proactive civic engagement demonstrates that their experiences have informed strong commitment to safeguarding democratic principles.

Even before the night of December 3, there were concerns about democratic backsliding in South Korea. What does the brief martial law episode tell us about the health of South Korea’s democracy?

For years, I have warned about the democratic backsliding in Korea, as detailed in my 2020 Journal of Democracy article, many op-eds in Korean papers, and a book, “South Korean Democracy in Crisis” (2022). The martial law episode can be understood in this larger context, though I could not imagine that such a thing could happen today. It is not 1979 or 1980, when Korea saw the last martial law under an authoritarian-military regime. The good news is that the swift civic response demonstrates the vibrancy of Korea’s democratic ethos. This episode highlights both the fragility and resilience of Korea’s young democracy.

This incident reflects a broader global pattern of democratic erosion but also showcases Korea’s unique strengths. Civic engagement, born from decades of resistance against authoritarianism, remains a cornerstone of the nation’s political culture. While I am concerned about the damage incurred before political stability is restored, Korea will eventually weather the current turmoil.

Polls show South Koreans’ views of Yoon and the martial law declaration are sharply divided based on political affiliation. How did political polarization set the stage for December 2024? How can South Korea start to bridge these gaps?

Korea’s political polarization has deepened over the past decade, setting the stage for the events of December 2024. A 2022 Pew survey showed that Korea had the strongest partisan conflicts in their society among the 19 countries considered – around nine in ten adults said there were strong conflicts between people who supported different political parties, including around half (49 percent) who said these conflicts are very strong. Yoon’s razor-thin victory over Lee Jae-myung in the last [presidential] election reflected such societal division.

Looking back, political polarization became increasingly worrisome during the Moon Jae-in administration that assumed power in the aftermath of the impeachment of President Park Guen-hye in 2017. Instead of pursuing national reconciliation of a society torn over impeachment, it led a ruthless campaign to “eradicate deep-rooted evils” (적폐청산), creating strong resentment among conservatives.

Political tensions grew further during the Yoon administration. The opposition-led legislation kept passing bills and measures that included impeachment of many high-ranking officials as well as criminal investigations of the First Lady, only to be vetoed by Yoon. Yoon justified the declaration of martial law as a necessary measure to restore public order from “anti-state forces” amid escalating tensions between political rivals. Korea today is deeply divided between pro- and anti-impeachment forces, with mass mobilization and counter-mobilization in the streets.

Thus far, Yoon has refused to cooperate fully with the investigation, claiming that it has violated the rule of law. He also galvanized staunch supporters who are fueled by YouTube conspiracy theories of election fraud and communist sympathizers. They criticize the impeachment as a politically motivated attack orchestrated by the opposition. These counter-strategies appear to be working. A recent poll shows that while the majority (59 percent) still supports Yoon’s impeachment, this figure marks a significant drop from the 75 percent reported in a poll conducted in early December. Furthermore, approval ratings of the ruling People Power Party (PPP) and the opposition Democratic Party (DP) are now practically tied, reverting proportional support back to the pre-martial law period.

Institutional reforms of the current “winner-takes-all” political systems are essential to bridging these gaps. I have long advocated for a parliamentary system that fosters coalition-building and compromise. A parliamentary system also lets the top leader step down if she or he loses public favor or the confidence of the legislature. Under the current system, there is no way to change the top leader unless she or he steps down or is impeached. Along with a parliamentary system, introducing a multi-member electoral system could also mitigate the stark binary divides of the current single member electoral arrangement that ultimately encourages polarization.

While most South Koreans recognize the need for such reforms, entrenched political interests have stalled progress.

South Korea had three presidents in less than two weeks, after the impeachments of Yoon on December 14 and then acting President Han Duck-soo on December 27. How has the political upheaval impacted governance in South Korea? Is the country equipped to handle a crisis like the deadly plane crash of December 29?

Korea’s political turmoil has earned it the moniker “The Acting Republic of Korea,” highlighting the instability stemming from rapid leadership turnover. This upheaval has significantly weakened governance, with adverse effects on the economy, foreign relations, and crisis management. Economic growth is projected at just 1.8 percent this year, down from the 2.2 percent July projection. On the foreign policy front, South Korea is not well-positioned to navigate its relationships with key partners, including the United States. The return of the Trump administration has introduced new uncertainties, particularly in areas such as trade, security, and alliances. For a country that relies heavily on stable international partnerships, the current political turmoil comes at a high cost.

Effective crisis management requires strong, stable leadership, which Korea currently lacks. While the country’s bureaucracy is capable and experienced in dealing with such emergencies as the plane crash, Korea needs to restore political stability and leadership to withstand future national crises.

Democratic Party leader Lee Jae-myung is viewed as the front-runner in the next presidential election – but he has been convicted in one case and faces other legal charges. Is it possible he could be barred from running? If so, how would the DP respond?

Lee’s candidacy is contingent on the outcomes of two political battles: the Constitutional Court’s decision on Yoon’s impeachment and Lee’s ongoing legal battles. Last November, he was convicted of violating election law, receiving a one-year prison sentence with two years of probation. Lee appealed to higher courts in hopes of overturning the ruling and remaining eligible for future elections. If the Supreme Court ultimately upholds Lee’s conviction before the Constitutional Court upholds Yoon’s impeachment, then Lee will be barred from running in the ensuing snap elections.

This scenario would be devastating for the Democratic Party (DP), forcing them to scramble for an alternative candidate. While a few viable options exist, none has Lee’s political stature or electoral appeal. That is why Lee’s supporters are working to delay his sentencing to ensure his eligibility, while Yoon’s allies are attempting to prolong the impeachment process to create a more favorable electoral environment.

The Supreme Court is unlikely to reach a final decision by mid-May, when a snap election may take place, though a ruling must be issued within six months from Lee’s initial sentence. This timing is critical because even if an intermediate appellate court upholds the conviction, Lee could still run for president, albeit under a cloud of legal uncertainty.

The PPP has attempted to defend Yoon, even though 12 party members voted for his impeachment. Given Yoon’s unpopularity, what are the prospects for the PPP moving forward?

Interestingly and quite surprisingly, despite Yoon’s impeachment and the PPP’s internal rift, approval ratings of both have recently improved, with polls showing 30-40 percent supporting them. This shift may indicate an increasing solidarity within the conservative voting bloc – not necessarily due to increased support for Yoon, but as a response to their unfavorable view of Lee Jae-myung and the Democratic Party. There is growing hope within PPP that they could stage a good fight against Lee in the snap election. Still, for the PPP to move forward, it must present a compelling vision for Korea’s future and rebuild public trust – a formidable task but a necessary one to remain competitive in the next election cycle.