What the Republic of Korea truly needs to safeguard its national security is a friendly neighborhood rather than the US' Terminal High-Altitude Air Defense system that will pose a threat to surrounding countries such as China. The decision of Seoul and Washington early last month to deploy the system on the Korean Peninsula will break the strategic balance in Northeast Asia, threatening regional peace and stability and signal the beginning of a new Cold War.

With THAAD's X-band radar commanding surveillance of an area of more than 1,900 kilometers from the peninsula, the United States can spy on almost half of China's territory and the southern part of Russia's Far East, endangering the two countries' national security.

The ROK's move represents a departure from its courageous shift from confrontation to cooperation to break the curse of the Cold War, highlighted by Seoul hosting the 1988 Olympic Games. The Seoul Olympics was a turning point in its history, which opened the road to economic prosperity thanks to a better security environment.

Good relations with its neighbors helped the ROK's economy tide over the Asian financial crisis in 1997 and the global financial crisis in 2008, and made it one of the big success stories not only in Northeast Asia but also the whole world. The ROK's geographical location has made its connections with China both necessary and convenient as the latter has become its biggest trading partner and biggest investment destination.

The ROK's annual trade with China has reached $300 billion, more than the combined total of its trade with the US, Japan and the European Union. Also, 60 percent of its trade surplus comes from China. The ROK's economy has benefited much from cooperation with China and the joint efforts of the two sides to maintain regional peace and stability.

Moreover, the ROK's membership of Beijing-initiated Asian Infrastructure Investment Bank and a bilateral free trade deal are expected to further deepen their economic ties. But Seoul's decision to deploy THAAD despite Beijing's strong opposition puts a question mark on that prospect.

A THAAD system in the ROK fits well into the US' planned missile shield against China in the Asia-Pacific region, but a shift in Seoul's 30-year commitment to regional peace and stability could damage its political mutual trust with Beijing.

Besides, as the ROK's nod to THAAD could prompt the Democratic People's Republic of Korea to expedite its nuclear program, a military confrontation looms on an already volatile Korean Peninsula.

Forgetting the horrors of war, ignoring the Cold War wounds, and ignoring the lessons learned from outside forces' intervention in the Middle East and North Africa, Seoul may face an outcome it is not capable of handling by jumping onto the US' rebalancing to Asia-Pacific bandwagon.