Thomas Maresca

Special for USA TODAY

SEOUL — Liberal Moon Jae-in won South Korea’s presidential election Tuesday after his two main rivals conceded, possibly opening a rift with the United States over relations with North Korea.

"I will build a new nation. I will make a great Korea, A proud Korea. And I will be the proud president of such a proud nation," the human rights lawyer told supporters in Seoul, the Yonhap News Agency reported.

Jeff Lee, 50, an international trader, was part of the crowd that gathered in the city's Gwanghwamun Square to cheer Moon's victory, staying until after midnight. “I came tonight to celebrate the new president,” said Lee, who lives in Seoul. Moon "is not a god but I think he’s trying to solve the problems. Then we can have a future.”

Moon's remarks came after conservative Hong Joon-pyo and centrist Ahn Cheol-soo conceded when an exit poll forecast Moon as the clear winner with 41% of the votes, ending nine years of conservative rule.

The election result was driven largely by domestic concerns over corruption and a slowing economy, but Moon has signaled a softer approach toward neighboring North Korea than his predecessor, the hawkish Park Geun-hye. Park, the nation's first female president, was impeached over corruption charges in March, triggering the election.

Moon, 64, has questioned the effectiveness of the strict sanctions against North Korea and left the door open for greater diplomatic and economic ties with the reclusive communist country.

"We can’t deny that the ruler of the North Korean people is Kim Jong Un,” Moon said in March. “We have no choice but to recognize Kim Jong Un as a counterpart, whether we put pressure and impose sanctions on North Korea or hold dialogue.”

Moon seeks to re-position South Korea in its dealings with North Korea. “We must lead the efforts to solve problems related to the (Korean) peninsula," he said during his campaign. "And our allies and neighboring countries, including the United States, should take on a role to support our leadership.”

North Korea's recent missile and nuclear tests have drawn strong rebuke from the United States, a longtime ally of South Korea.

The White House congratulated Moon on his election Tuesday. White House press secretary Sean Spicer said the administration looks forward to working with Moon “to continue to strengthen the alliance” between the U.S. and South Korea.

President Trump has talked tough against North Korea, hinting at military action to end its nuclear and missile threats. His comments raised fears of possible retaliation by the North against the South Korean capital of Seoul, a metropolitan area of 25 million a mere 35 miles from the border.

Moon has also criticized the U.S. deployment of an anti-ballistic missile defense system known as THAAD (Terminal High Altitude Area Defense) in South Korea, a military move Park had endorsed. The U.S. began deploying elements of THAAD in late April outside of Seoul and announced it was operational last week.

Moon argued that the U.S. should have waited for a new president to make the final decision to install the $1 billion system, which the Pentagon apparently rushed to make operational for fear Moon might block it if elected.

Trump rattled U.S.-South Korea relations in a recent interview with Reuters when he said he wanted South Korea to pay for the cost of THAAD. "We're going to protect them," Trump said. "But they should pay for that, and they understand that."

Trump also said he planned to renegotiate or scrap the free-trade pact between the U.S. and South Korea, calling it a “horrible” deal.

While Moon's foreign policy positions could alter the dynamics in the region and with the U.S., the election results in many ways were fueled by a strong backlash against Park.

"At the end of the day, this election is the capstone of the (Park) impeachment,” said John Delury, an associate professor at Yonsei University Graduate School of International Studies in Seoul. Moon "is seen as clean. That’s one way his candidacy makes a lot of sense. He’s the anti-Park Geun-hye, he's the furthest away from her while still being a mainstream choice.”

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