Since the end of the Cold War, the United States has been reconstructed alliance system to maintain global hegemony in the Western Europe, the Middle East and the Asia-Pacific region. Among them, the US-ROK alliance is the important part in the Asia-Pacific region. Experienced a baptism of fire and more than sixty years through thick and thin,the US-ROK alliance several adjustments, remains timeless. After the Cold War, North Korea’s security threat has decreased, but with continuous fermentation Korean nuclear issue and the issue of missiles, security pressures faced by US-ROK alliance is not only no "end of history", but a "history repeat ". experienced baptism of the Cold War and the precipitation of the post-Cold War,the US-ROK alliance once again reveal the coldness dazzling of military alliance in the 21 st century, which forced people to think about and answer carefully to the following question:With the acceleration of the strategic steps of center of gravity to the east, US-ROK alliance appeared what specific changes? What is the status of US-ROK alliance in American asia-pacific security alliance system? As the DPRK nuclear issue fermentation and the interaction of China-US relations, US-ROK alliance in the future development trend is going to be? US-ROK alliance on Northeast Asian security in the21 st century will show what kind of shape?In order to answer these questions, this article will discuss the necessary six chapters unfold.The first chapter elaborates the history and reality cognition of the US-ROK alliance. In the cold war hot war, the US and South Korea concluded an alliance. This chapter describes the evolution of the US-ROK alliance from a military, economic and concept.And in the dimension of history has assessed the impact of three levels of alliance. In the 21 st century, from their points of view on the United States and Korea under the US Asia-Pacific rebalancing background allies strengthen the motivation to do a detailed analysis. Further pointed out that although the US-ROK alliance further strengthen, throughout the years the DPRK nuclear issue and Northeast Asia political and ecological deterioration, telling volumes that US-ROK alliance didnot achieve the desired results of strengthen.The second chapter expounds the concept extension of the US-ROK alliance. Its meaning is extended mainly in five aspects of conventional military cooperation,intelligence cooperation, nuclear cooperation, missile cooperation, network and space cooperation. The two countries strengthen cooperation in the field of conventional military defense cooperation in trade, the Navy, the Air Force; intelligence cooperation,the United States continued to provide strategic and tactical intelligence Korea itself can not be obtained, by virtue of its geographical advantage to play South Korea in the United States an important global intelligence system role; nuclear energy cooperation,US and South Korea new nuclear cooperation agreement is no longer expressly limit the Korean uranium enrichment and reprocessing of spent fuel(this conclusion is accurate,and then verify); aspects of missile cooperation,the US gradully deregulate the offensive missiles of South Korea, still the US-ROK cooperation in missile US-led;Follow the field of network space, with the advance of the US-ROK bilateral cooperation in space cooperation, the United States concerns have decreased on South Korea’s development of space technology related to missile proliferation and export control issues.The third chapter introduces the mechanism expansion of the US-ROK alliance.Early 21 st Century US-ROK alliance expansion mechanism is mainly reflected in the US-ROK security cooperation mechanism and the mechanism of the US-ROK economic and trade aspects. US-ROK security cooperation mechanisms include security cooperation meetings and military exercises, the US-ROK security cooperation in the early 21 st century has been expanded not only in meeting the existing strategic security cooperation meeting on the 20 th century, and also increase the security cooperation level meeting on specific topics. In the 21 st century, the US-ROK alliance not only increase the number of military exercises in the strategic and operational level, and the number of aircraft involved in the exercise has increased; regulating the military structure of the alliance before and after the transfer of wartime command and joint command and control system based on the "SA2015"; the chapter also discussed the2014 proposed conditions of wartime command transfer in-depth analysis.The fouth chapter analyzes the functions and difficulties of the US-ROK alliance.US-ROK alliance function and interaction difficulties exist interaction. US-ROK alliance has a deterrent function, barrier function and radiation. US-ROK alliance and the presence of a new alliance of traditional alliance dilemma predicament. Traditional allies plight US-ROK alliance refers to abandon the traditional difficulties involved with traditional US-ROK alliance dilemma mainly from differences in strategic objectives,cost-sharing and other issues were discussed at two levels. Subsequently, this chapter focuses on the new plight of US-ROK alliance, that the identity plight between the opponent and economic partners,and the plight between the alliance within the same alliance system.The fifth chapter discusses the relationship between the US-ROK alliance and countries in Northeast Asia. Respectively, discussed the US-ROK alliance with Korea,Japan and China. From two aspects of the US-ROK alliance and the North Korean nuclear issue, the US-ROK alliance and unified peninsula to discuss the relationship between the US-ROK alliance and North Korea; and from the security and concept of two levels to analyze the relationship between Japan and US-ROK alliance, and to explore the the possibility of United States, Japan and korea trilateral alliance; from the security, economic, on the concept of three levels to analyze the relationship between US-ROK alliance with China.The sixth chapter discusses the relationship between the US-ROK alliance and Northeast Asia regional regime. Respectively, from two aspects of the US-ROK alliance and security mechanism in Northeast Asia, the US-ROK alliance and economic mechanism in Northeast Asia to explore the relationship between the two. From the two aspects of the missing of US-ROK alliance and security mechanism in Northeast Asia,the role of the US-ROK alliance with the Six-Party Talks in Northeast Asia security mechanism on the relationship between the US-ROK alliance and Northeast Asian security mechanism is discussed; from the US-ROK FTA on Effect CJK FTA, the Korean accession to TPP impact on China-Japan-Korea FTA and the like to analyze the relationship between the US-ROK alliance and Regional economic cooperation mechanism. |