When Yoon Suk Yeol was running for president, he had the word “king” written on his palm. South Koreans dismissed — and ridiculed — it as a shamanistic ritual that reflected his desire for top government office.
But after his inauguration in May 2022, it didn’t take long for them to see an authoritarian streak in Mr. Yoon.
On short notice, he moved the presidential office from the graceful Blue House to a drab military building. When he turned 63 in December 2023, his security team sang songs honoring him as “a president sent from Heaven” and describing his “845,280 minutes” in office so far as “a time blessed.” Two months later, a college student who protested Mr. Yoon’s decision to cut government budgets for scientific research was gagged and dragged out by the president’s bodyguards. When journalists published what he called “fake news,” prosecutors raided their homes and newsrooms to collect evidence.
Mr. Yoon kept pushing the envelope, until he made his fatal mistake: On Dec. 3, he declared martial law, threatening a deeply cherished part of South Korean life: democracy.
To South Koreans, democracy has never been something given; it was fought for and won through decades of struggle against authoritarian leaders at the cost of torture, imprisonment and bloodshed. All the major political milestones in South Korea — an end to dictatorship, the introduction of free elections, the ouster of abusive leaders — were achieved after citizens took to the streets.
So when people saw troops sent by Mr. Yoon storming the National Assembly to seize the legislature by force, their response was immediate. But unlike those who fought government repression in the 1950s through the ’80s, South Koreans protesting in recent months had democratic institutions on their side.
The current Constitution, written in 1987 after a huge pro-democracy uprising, gave the National Assembly the power to vote down martial law and impeach presidents. The Constitutional Court, created under that Constitution, got to decide whether to remove or reinstate an impeached president. And leaders democratically elected under that Constitution imprisoned those who had earlier taken power by military force.
Younger generations, including the paratroopers Mr. Yoon sent to seize the Assembly in December, grew up learning of that history through box office-hit movies and novelists like the Nobel laureate Han Kang.
On Dec. 3, the troops hesitated before angry citizens blocking them with bare hands, allowing time for lawmakers, including some members of Mr. Yoon’s own party, to gather and vote to lift his martial law decree. The Assembly then impeached him, on Dec. 14.
And on Friday, the Constitutional Court’s eight justices, including those appointed by Mr. Yoon or his party, unanimously upheld that impeachment, putting an end to his military rebellion.
To one observer, these events were a victory for the democratic institutions created in the late 1980s. “The response to Yoon’s attempted coup d’état displayed the maturity of Korean democracy — first of all, the resilience of civil society, which reacted immediately and massively to oppose the coup, most notably with the passion of Korean youth who were not alive in the 1980s and experienced the dangers of a return to autocratic rule for the first time,” said Daniel Sneider, a former journalist who covered South Korea back then and is now a lecturer at Stanford University.
“The fact that it was a unanimous decision of the Constitutional Court, with conservative appointees joining the decision, was a very important expression of not only the clarity of the case, but also the ability to overcome ideological polarization,” Mr. Sneider said.
Mr. Yoon’s power grab also exposed the vulnerabilities of democracy in South Korea. If such a thing can happen in a nation long considered an exemplary case of democratization in Asia, scholars warned, it can happen elsewhere, too.
Despite his removal, the deep polarization that led up to Mr. Yoon’s declaration of martial law persists. The partisan struggle between the left and right is likely to intensify in the next two months as the country lurches toward a presidential election.
But the past four months have also shown the resilience of South Korean democracy.
Until Mr. Yoon came along, few South Koreans thought that a return to military rule was possible in their country, a peaceful democracy known globally for its cars, smartphones and K-dramas. Many of those who joined protests calling for Mr. Yoon’s ouster in recent weeks said they had been more proud of their democracy than of their cultural exports like the boy band BTS or the Netflix hit “Squid Game.”
When Mr. Yoon hurt that pride, he picked a fight he couldn’t win. During rallies, people shared a video clip of former President Kim Dae-jung, an iconic figure in South Korea’s democratization struggle.
“Democracy is not free,” Mr. Kim said in the clip. “You must shed blood, sweat and tears for it.”
If the Constitutional Court had voted to reinstate Mr. Yoon, South Korea would have seen a “second wave of democratization movement” and “a second Gwangju,” said Cho Gab-je, a prominent South Korean journalist who has covered the nation’s political evolution since 1971, referring to the brutally suppressed uprising against martial law in the southern city of Gwangju in 1980.
“We had our share of martial law, but Yoon Suk Yeol was the first president to send armed troops into Parliament,” Mr. Cho said.
Mr. Yoon was once a hero among South Koreans. He built his national image as an uncompromising prosecutor when he helped imprison two former presidents for corruption. But he proved disastrous as a politician — unable to engage in the give and take of compromise with the opposition, which controlled the National Assembly.
He was accused of filling his presidential staff with officials too timid to speak up. He was nicknamed “Mr. 59 Minutes,” because that was how long he was said to speak during an hourlong meeting. He rarely apologized for his wife’s scandals or even for deadly disasters. He used his veto power to kill opposition bills. The opposition slashed his budgets and impeached an unprecedented number of political appointees in his government.
“A player busy playing on the field doesn’t look at the electronic scoreboard,” Mr. Yoon once said when asked about his dismal approval ratings.
Such an attitude allowed him to push unpopular efforts, such as improving ties with Japan and drastically increasing the number of doctors. But even many who sympathized with his struggle against the opposition didn’t see martial law coming.
“Koreans do not want the 1980s option, when martial law and tear gas made forcibly disappeared people painful to so many families,” said Alexis Dudden, a professor of history at the University of Connecticut. “Yoon and his advisers missed the mark of reading today’s South Korea in many obvious ways.”