SEOUL -- In his successful run for South Korea's presidency, liberal Moon Jae-in was the chief beneficiary of the public's animus toward his predecessor, disgraced conservative Park Geun-hye. To an extent, a contingent of supporters one newspaper dubbed a "digital terror" helped use that anger against Moon's critics.
Less than a month before the May 9 election, on April 19, presidential hopefuls squared off in a televised debate. Sim Sang-jung, of the left-wing Justice Party, lashed out at Moon, the Democratic Party of Korea candidate.
This earned Sim an online lashing of her own from ardent Moon backers, known as the "Moonpa." Her party's blog was flooded with condemnations. "Why do you reproach him more bitterly than Park Geun-hye?" one commenter wrote.
Moon's core supporters appear to be mostly 30-somethings who have had it with South Korea's widening income gap and harsh job market. His pledge to clean up the "deep-rooted evils" in society resonated with them.
During the campaign, many took to the internet to fight for their man. Any criticism of Moon would trigger calls for an online protest, which would quickly spread via social media, emails and blogs.
Supporters of other presidential candidates made their presence felt online, too. But the Moonpa's attacks were so fierce that the Maeil Business Newspaper used "digital terror" to describe them in an editorial.
Song Min-soon, a former South Korean foreign minister, also found himself in the crosshairs of the Moonpa.
Song disclosed a document to back up his allegation that Moon consulted with Pyongyang in advance when, in 2007, Seoul abstained from a United Nations vote on human rights in the North. At the time, Moon was the chief of staff for then-President Roh Moo-hyun.
Song's blog was soon inundated with critical posts. "What are your ulterior motives?" asked one.
Face of change
The Moonpa are only part of the story of how Moon rode anti-Park sentiment all the way to the Blue House, with 41.1% of the vote. You could say he was the right man, in the right place, at the right time.
The influence-peddling scandal that led to Park's impeachment and removal from office, involving her longtime confidante Choi Soon-sil, unleashed an intense wave of public anger. Many South Koreans also resented how Park had opened up to Choi while shying away from dialogue with regular citizens.
At the end of last year, a massive "candle rally" was held at Seoul's Gwanghwamun Square to demand Park's resignation. The organizers estimated the crowd at 1 million. The phrase "anything but Park," or "ABP," soon became ubiquitous.
At first glance, Moon might not have been the most likely candidate to tap into that anger. The former human rights lawyer comes across as even-tempered. One might even say he lacks charisma, unlike his late ally, former President Roh.
But as the largest opposition group in the Park era, the Democratic Party of Korea was ideally positioned to become the symbol of change. That gave Moon a clear path to victory.
"I don't necessarily adore him," a university student said of Moon two days before the election. "But I probably feel more strongly that I can't forgive Park Geun-hye."
The student was watching Ahn Cheol-soo, another prominent presidential candidate, give a speech near Hongik University in Seoul. Asked which candidate he supported, he paused for a while before naming Moon.
Ahn, a centrist, was thought to have a shot at winning. He tried to turn the tables on Moon, who was ahead in the polls, by courting conservatives who were abandoning Park's Liberty Korea Party. But that strategy was not enough to allow Ahn to catch the anti-Park wave.
As one person close to Ahn's campaign put it regretfully, "The head of Moon Jae-in's supporters' group was [effectively] Park Geun-hye."