Despite China's vehement protests against the planned deployment of the U.S. THAAD missile defense system in South Korea, the decision is not expected to do lasting harm to Seoul's relations with Beijing, a U.S. expert said Friday.

South Korea and the U.S. announced earlier that they have officially decided to deploy a Terminal High Altitude Area Defense battery to South Korea to cope with ever-growing nuclear and missile threats from North Korea.

China, which has long voiced opposition to THAAD in the South, strongly protested the decision, saying the deployment does not help achieve the denuclearization of the Korean Peninsula and hurts peace and stability in the region.

"Deciding to move ahead with THAAD has not been easy for Seoul due to both international and domestic factors. But deployment of THAAD is a sensible military response to North Korea's missile threat," Alan Romberg, a distinguished fellow at the Stimson Center, told Yonhap News Agency.

Despite China's strong objections, it will come to acknowledge that it is a legitimate defensive tool for Seoul, the expert said, adding that South Korea and the U.S. should make greater efforts to clarify the role of THAAD even though recent offers to brief Beijing in detail have so far been rejected.

"The ROK is an important partner for China, as China is for the ROK, so I do not believe there will be lasting harm in that relationship," he said. "Both the Russian and Chinese reaction will be more directed at the United States than at the ROK."

China has long claimed that THAAD, especially the powerful X-band radar that comes with the system, can be used against it, despite repeated assurances from Washington that the system is aimed only at deterring North Korean threats.

While announcing the deployment decision, the U.S. Defense Department said emphatically that THAAD will be "focused solely on North Korean nuclear and missile threats and would not be directed towards any third party nations."

North Korea's fourth nuclear test in January and the long-range rocket launch the following month provided a strong impetus for the U.S. and South Korea to move ahead with formal discussions about the potential placement of THAAD in the South.

Up until then, Seoul had been very cautious about the issue, mindful of China's intense objections.

Romberg said it makes no sense to argue THAAD is "an unwarranted response" to the North Korean threats.

"China is focused on larger strategic issues such as the maintenance of stability and avoidance of war, and while it will want some assurances that the ROK does not view its alliance with the United States as a vehicle for confronting the PRC, the issues involved there are both larger and more political than THAAD," he said.

"Moreover, Beijing will continue to take some measures to pressure Pyongyang into halting its nuclear weapons program, with all the dangers that program presents to China," he added.

Robert Manning, a senior Asia affairs expert at the think tank Atlantic Council, said that the THAAD deployment is important in strengthening deterrence, the U.S.-South Korea alliance and advancing trilateral strategic cooperation between the U.S., the South and Japan.

"China is more concerned about U.S.-ROK-Japan intelligence and strategic cooperation than THAAD capabilities. Despite their rhetoric, Beijing knows that THAAD does not affect its 2nd strike nuclear capabilities," he said in comments to Yonhap.

"It is very arrogant for China to support and enable North Korea, downplay the threat and tell the ROK they cannot defend themselves. China seems to want the ROK to put China's interests ahead of its own. This has generated anger in the ROK," he said.

Despite the protest, China remains concerned about North Korea and is expected to cooperate with the U.S. and the South on North Korea, he said.

Bruce Klingner, a senior Korea expert at the Heritage Foundation, welcomed the THAAD decision, saying it is better than any system the South has or will have for decades and would enhance protection of South Korean people and American troops in the South.

"A careful assessment of the range/altitude of the THAAD interceptors and X-band radar clearly shows it does not impact Chinese or Russian strategic interests. Therefore, Beijing’s and Moscow’s protests are disingenuous and politically-motivated,"

Klingner said.

"Quite simply, Beijing wants the Republic of Korea to be at greater risk from its North Korean ally. Seoul quite properly rejected Chinese pressure and economic blackmail and stood up for its national interest," he said.

Experts pointed out that THAAD is not a panacea against North Korean threats.

Michael Elleman, a consulting senior fellow at the International Institute for Strategic Studies, said that THAAD could greatly enhance South Korea's capacity to block a substantial fraction of missiles emanating from North Korea, but cannot provide absolute protection against a nuclear attack from the North.

"Moreover, Pyongyang will almost certainly begin to devise countermeasures to help limit the impact of this deployment, including launching missiles in large salvos to overwhelm the defenses," he said in comments provided by the 38 North website.

Joel Wit, editor of 38 North, also said that the THAAD decision would inflame tensions.

"While the deployment of THAAD is a necessary measure given the growth of North Korea’s nuclear and missile inventories, this step is only likely to widen the gap between the United States and China over a strategy to deal with the dangers posed by North Korea," Wit said. "It is essential that Washington and Beijing find cooperative paths forward, or else regional tensions are only likely to increase." (Yonhap)