The recent protests and demonstrations in South Korea against its government's decision over the deployment of the Terminal High Altitude Area Defense (THAAD) system showed a society splitting over the issue. Arguments on whether to deploy the US-built missile shield are nothing new for the nation. Over the past few years, controversies and disputes on this have appeared whenever there were negotiations and consultations about THAAD deployment between Seoul and Beijing or Washington.

China has firmly opposed the deployment of THAAD in South Korea, because such arrangement will not only do no good to peace and stability on the Korean Peninsula, but also severely break the already fragile strategic balance in the region, while posing a threat to China's strategic security.

The installation of THAAD will inevitably spark the escalation of tensions on the peninsula, trigger a new round of negative security competition - enhancing one's own safety by wrecking the other's security interests.

Such a vicious cycle has been putting on the stage by two sides of the peninsula for over two decades. Whenever one of them adopted provocative actions, the other would immediately take countermeasures, making the former resort to more offensive steps. In the end, the two sides create more insecurity for each other. Now Seoul counts on THAAD to guard South Korea from risks from the North, yet the deployment will only end up in another round of tension and an arms race.

The bigger problem is, the deployment of THAAD will objectively hitch Seoul to the US security wagon. The White House has been utilizing the North Korean missile threat to build its own missile defense system in Northeast Asia. Its ultimate goal is to establish a global missile defense system in both sides of not only Atlantic Ocean, but also the Pacific. Setting up THAAD on the peninsula is a crucial part of it, and will enable Washington to complete its missile defense system with low-, medium- and high-altitude defensive shields, which will greatly boost the US ability to receive advance warning of any attack as well as intercept Chinese strategic weapons, and build a missile defense wall in the east-wing of Russia. Obviously, this will fundamentally smash the strategic balance among China, the US and Russia. Once the regional strategic balance is broken, there will be no security for Seoul.

That said, THAAD deployment is not only an inter-Korean matter, but will provoke strategic competition and arms race among major powers, which will eventually jeopardize Seoul's security.

In terms of the use and technological reliability of THAAD, the US has not told the truth to South Korea. The deployment was to a large extent hyped up by Raytheon Company, the primary contractor of the THAAD system. Raytheon's biggest concern is not realistic issues like whether the shield can actually protect South Korea from Pyongyang's missiles, but about huge profit. In this regard, both the Pentagon and the US Department of State have apparently helped fan the fire.

When Seoul and Washington jointly made the decision, there was no scientific proof that THAAD can effectively protect South Korea. Even US missile experts admitted the system "cannot provide absolute protection against a nuclear attack from the North," but will turn into a vital pillar of US military presence in the region. In another word, before figuring out whether THAAD is capable to safeguard South Korea, the latter has already made a decision to disrupt its own security atmosphere.

Seoul and Washington made the same decision with different goals - South Korea hopes to defend itself from missiles from the North while the US aims at its own global missile defense system. Indeed, the Blue House should have reacted to the nuclear threat from Pyongyang, yet it failed to make the right choice.

In this case, the initiator is Washington, who has broken the strategic balance in the region. China must hence adopt its own version of a rebalancing strategy. For instance, it can improve the strike ability of its own missiles, enhance its missile's capability of jamming THAAD's radar as well as the ability of knocking out the systems in the attacks, establish its own missile defense capacity, or develop its own hypersonic strike weapons and drones for long-range attacks, so as to make US global missile defense system end up as a 21st-century Maginot Line.

Policymakers in the Pentagon are perhaps pleased for making Seoul obedient this time. However, once deployed, how other major powers will respond to the threat of THAAD is not up to Seoul or Washington.

The author is a senior research fellow at the China Institute of International Studies. opinion@globaltimes.com.cn