South Korea's Ministry of National Defense said Sunday it will formally discuss deploying the THAAD missile defense system with the US, after North Korea claimed to have launched a satellite into space. Seoul's decision will further complicate the security situation of Northeast Asia.

South Korea said one THAAD battery costs about 1.5 trillion won ($1.3 billion), and the US will cover the costs of deployment, operation and maintenance. One battery is capable of shielding half to two thirds of the South Korean territory.

It is widely believed by military experts that once THAAD is installed, Chinese missiles will be included as its target of surveillance, which will jeopardize Chinese national security. South Korea explained that North Korea is the only target of the system and this doesn't impose threat to China's national security. However, such explanation is feeble and futile.

The discussion over THAAD deployment in South Korea has been lasted for over a decade. The Chinese authorities have been explicitly opposed to it. In light of China's opposition, South Korea, although it was considered  "willing to deploy" the system, didn't agree to the deployment. South Korea publicly stuck to "Three Nos" on the THAAD issue: that there has been no request from the US, no negotiations with the US, and no decision made.

The abrupt attitude shift at a confusing moment caused by North Korea's test of a long-range missile is a decision of no strategic vision. For the sake of its security, Seoul took an impetuous action, giving no consideration to the long-term strategic impact.

Pyongyang embarked on a wrong path due to its sense of insecurity. The deployment of THAAD in South Korea will not put an end to the vicious interaction of varied forces in the region, only causing more troubles to Northeast Asia. Seoul now is at the center of a situation that is spiraling out of control.

China is close to the Korean Peninsula, and falls victim to any tensions in the region. However, China is not in a position to direct the situation. China's advocacy for de-escalating the tensions has not been well responded.

If the nuclear issues in the Korean Peninsula keep spiraling downward, China has no choice but to brace for the worse scenario. China will reinforce its capability to cope with the Korean Peninsula from going out of control, including dealing with military threats from THAAD.

If THAAD takes root in South Korea, it will be officially considered as a target of research by the Chinese military from both the strategic and tactical dimensions. We cannot be easily convinced by South Korea and the US that the system only aims to deter North Korea. We should take a realistic position to observe South Korea's national strategy.

There have been an increasing number of uncontrollable factors in China's periphery, with the US constantly stirring up in the security field. China should enhance its comprehensive defense strength to deal with these challenges. The degree of China's strength will determine the nature of these challenges.

For example, the deployment of THAAD may not be a major threat to China, because China's capability in developing strategic missiles can easily overcome the deterrence imposed by South Korea and the US through THAAD. It is the US and South Korea that hold the initiative of building THAAD, while the former can be achieved through our own efforts.

Missile defense systems have never been used in a practical war of major powers, and their effects remain theoretical. They have played a strategic deterrent role in the past, and served as a political connection between the US and some of its allies. Some scholars believe that deploying THAAD in South Korea has more political significance than military significance.

Maybe in the end, China won't be able to stop the deployment of THAAD, but whatever the result is, China should firmly oppose. The tensions in the Korean Peninsula might escalate and even come to a showdown. In this scenario, there could hardly be an all-round strategy that won't harm the interests of any party. However, China's determination to safeguard its national security should be clearly shown, so that the other stakeholders will have to think carefully before they make any decision that might challenge China's position.