In a stunning blow for US diplomacy in the Pacific rim region, Yonhap reported that South Korea’s newly elected president, Moon Jae-in said he has suspended the deployment of American THAAD anti-missile defense system, a major concession to China and a significant break with the United States on policy toward North Korea.

“We are not saying the two launchers and other equipment that has already been deployed should be withdrawn. But those that have yet to be deployed will have to wait,” a senior presidential office official said, according to the news agency. The remarks come as the presidential office is examining an allegation South Korea’s defense ministry may have kept the delivery of four further Thaad launchers secret in an attempt to protect the project from an environmental impact evaluation, Yonhap said.



Protesting the American missile defense system in Seoul, last week

As noted previously, the THAAD missile defense system has been controversial in South Korea where thousands have protested the deployment, while also drawing sharp criticism from China, which views the system’s radar as a threat to the regional balance of power. In response to the initial deployment, Beijing had taken retaliatory economic measures against Seoul, including curtailing the flow of Chinese tourists and punishing South Korean companies in China. The defense system officially went into operation late last month on an abandoned golf course in Seongju, 135 miles southeast of Seoul, when two of six launchers were installed. United States military officials have said that the system is already “operational and has the ability to intercept North Korean missiles.”

During his presidential campaign, Moon who won the South Korean presidency last month and has adopted a conciliatory pose in the ongoing North Korean conflict, complained that the United States and the previous South Korean administration rushed to deploy Thaad before the election.

Moon's decision to suspend the installation will strain relations with the White House, which has taken a hard line in confronting North Korea and its nuclear weapons program. It could also raise concerns about United States efforts to present a tough, unified position with Japan and South Korea against the North. Even more striking is that Moon also suggested that South Korea must “learn to say no” to Washington. He has already signaled a softening stance toward North Korea by encouraging aid groups to visit the country, although the North has rejected those offers since Seoul supported new United Nations sanctions.

Cited by the NYT, analysts said that as protesters demonstrated against the Thaad installation and South Korean businesses pressured the government to improve relations with China, Moon may have decided that suspending the progress of the missile defense system was politically expedient.

“I think he is trying to find a diplomatic way to slow down the process to placate the business community and placate his political supporters,” said Stephen R. Nagy, senior associate professor of politics and international studies at International Christian University in Tokyo.

Just as important as the distancing from the US is the apparent concession to Beijing: Moon may have sensed that China was not going to back down. When Lee Hae-chan, South Korea’s special presidential envoy, visited Beijing last month, President Xi Jinping did not concede anything during a meeting they jointly oversaw. As the NYT adds, China’s strategy is to stand firm in its objections to Thaad to force Mr. Moon to modify — or even eliminate — a missile defense system that the Chinese suspect he does not like, either.

Opponents of Moon said the suspension was probably a first step toward rejecting the missile defense system altogether. Oh Shin-hwan, a spokesman for the conservative-leaning Bareun Party, said in a statement that because the environmental review would take more than a year to complete, “the government does not intend to deploy the remaining four launchers.”

Discussing Moon's decision, Scott Snyder, director of the program on United States-Korea policy at the Council on Foreign Relations, said that American officials should explain the need for the defense system to the new administration and that Moon’s supporters should not reject it simply because Ms. Park had approved it or give in to pressure from China.

“Thaad is at risk of becoming overpoliticized,” Mr. Snyder wrote. “And both sides need to take a deep breath and reaffirm common objectives and means for dealing with them rather than allowing Thaad to become a neuralgic and reflexive object of confrontation.”

In retrospect, it now appears too late to avoid "overpolitization", especially with China scoring a major diplomatic victory in the ongoing battle of influence between the US and Beijing over South Korea's decisionmaking process.