Study On The Causes For The Deployment Of THAAD In South Korea From The Perspective Of U.S.-ROK Alliance

THAAD--the abbreviation of Terminal High Altitude Area Defense,is one of USA's advanced defense systems,which can intercept medium and long-range missiles.At the end of the Obama administration,the United States started to deploy THAAD in South Korea under the pretext of dealing with North Korea's nuclear and missile threat.However,it can not effectively cope with North Korea's military threat,on the contrary,due to countermeasures from China and Russia,the Northeast Asia will have a more tense situation,and the Sino-ROK relations will also deteriorate,under this circumstance,South Korea will encounter a worse security environment.Therefore the deployment of THAAD in the ROK is the mismatch of ROK's security strategy.Based on the theory of Geopolitics,this paper analyzes the complex reasons for THAAD's deployment in the ROK from the perspective of US-ROK alliance for the purpose of expounding the dilemma of the ROK's designing security strategy.In 1953,the United States and South Korea signed the Mutual Defense Treaty,which defined USA's obligations to assure South Korea's security from a legal perspective.Accordingly,the United States has fulfilled its obligations through a number of measures during the Cold War,such as the stationing of troops in South Korea and the deployment of nuclear weapons and other strategic assets.After the collapse of the Soviet Union,the United States withdrew its nuclear weapons from South Korea.However,it did not rescind the Mutual Defense Treaty,which means that the United States maintained the Cold War mechanism on the Korean Peninsula.Due to the collapse of the Soviet Union,DPRK lost the protection of big power's nuclear umbrella,the alliance between the United States and South Korea is a realistic threat to North Korea's national security.In this case,North Korea can only pursue self-help for its security.Since the nuclear weapon is a complex carrier of military strikes,strategic deterrence,political power and economic exchanges,the DPRK has chosen to develop it.With the efforts of than 20 years,it has accumulated a certain amount of nuclear capability.In order to cope with North Korea's nuclear threat,the United States has increased its military presence in the Asia-pacific region,improved its allies' military strength including South Korea and Japan,and attempted to curb North Korea's nuclear development through sanctions.In addition,the United States has improved its missile defense system in this region,the deployment of THAAD in South Korea is part of the system.However,the main threat to South Korea from North Korea is conventional weapons such as short-range missiles and artilleries.It is clear that THAAD goes far beyond the need in the peninsula's security and defense.Given THAAD's long-range surveillance and defense capability,the strategic intention of USA's deployment of THAAD in South Korea is to contain China and Russia.From the deployment of THAAD in South Korea,it can be inferred that South Korea's security strategies must serve the U.S.regional and global strategies,which is determined by South Korea's subordinate status in the US-ROK alliance.Meanwhile,South Korea's economic dependence on China and its security dependence on the United States have inevitably led it to a "choice dilemma" in the scenarios of competition between China and USA.All these factors show that "Rimland States"will inevitably fall into the dilemma of strategic choice in the state of division and confrontation.To solve this problem,it may be their best choice to achieve national independence and avoid the intervention of external powers.