The People's Republic of China's (PRC's) two basic considerations in forming a South China Sea policy are China's domestic situation and the regional international environment. In the early stage of PRC history, the Beijing government was too busy with power-consolidation campaigns to attend to affairs relating to the islands in the South China Sea. However, the desire to become a sea power and changes in the regional situation led Beijing to wish to expand into the South China Sea. First, successive outbreaks from the end of World War Ⅱ to the 1970s-including the Korean War, the artillery war across the Taiwan Strait, and the Vietnam War-enabled the United States to gain leadership as well as control over the sealanes of communication in the Western Pacific, thus imposing constraints on the PRC's expansion into the South China Sea. Second, the PRC navy has developed slowly and has so far been unable to expand into blue waters. The PRC's emphasis, therefore, has always been on coastal defense and its policy toward the South China Sea has been defensive by nature. In the post-Cold War era, a multilateral security mechanism has emerged in the Asia-Pacific region and member states of the Association of Southeast Asian Nations (ASEAN) have also proposed to conclude a code of conduct on the South China Sea. Although having so far insisted on resolving the the Spratly (Nansha) Is lands dispute through bilateral talks, Beijing may modify its South China Sea policy when substantive negotiations for the Code of Conduct on the South China Sea are held.