As South Korean lawmakers attempted to impeach President Yoon Suk Yeol for declaring martial law, ruling party MPs exited the chamber to block the effort—except for Ahn Cheol-soo.

Ahn, a self-made millionaire, trained doctor, and software designer, was one of only two members of the ruling People Power Party to vote in favor of removing Yoon from office.

Despite tens of thousands of protesters outside demanding the leader's removal after he deployed soldiers in helicopters to parliament to overturn civilian rule, the impeachment motion failed without meeting the quorum.

Days earlier, lawmakers from both parties had united, barricading doors and confronting special forces troops, to counter the martial law declaration.

However, the ruling party then consolidated its stance, claiming that Yoon promised to resign and transfer power to the prime minister and party chief—actions the opposition denounces as unconstitutional.

Ahn faced boos and heckles during a party meeting when he argued that the president needed accountability.

"The concept of a president staging an unconstitutional coup is unimaginable," Ahn told AFP, reflecting on his decision.

Yoon's approval rating dropped to 11%, and more protests are anticipated, even as the opposition prepares to renew impeachment efforts.

Ahn felt a "sense of duty" to uphold constitutional order as he cast his decisive vote, dedicated to representing public will over personal or party interests.

Having previously aspired to be president—competing in the 2022 election before supporting Yoon—a move crucial for Yoon's narrow victory, Ahn now stands at odds with his party.

The People Power Party blocked impeachment, asserting that Yoon would eventually step down, but provided no timetable.

Discontent with this ambiguity, Ahn deemed impeachment necessary.

"Every MP is a constitutional agent," Ahn asserted, explaining that conscience takes precedence over party directives.

He insists Yoon has lost confidence across the public and international allies, necessitating immediate resignation plans.

A notable figure in South Korea, Ahn gained prominence well before politics, having founded AhnLab, the leading antivirus software company in the country.

His strategic endorsement of Yoon in 2022 was pivotal, reflecting a decision he now regrets.

"If we had known what we know now, we could not have voted for him," Ahn stated, criticizing the president's actions.

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