南海主權爭端近年成為地區矚目的焦點,且呈現國際化、複雜化、擴大化的趨勢,尤其特殊的戰略價值,也攸關美國的戰略利益。東南亞地區在20世紀初期就已經是美國傳統勢力的範圍,從1898年西班牙將菲律賓轉讓給美國開始,逐步形成在該地區的勢力範圍。冷戰期間,美國分別在菲律賓以及越南擁有眾多的基地和大量的駐軍,以制衡前蘇聯的軍事擴張。1973年美軍撤出越南金蘭灣海、空軍基地、1992年再撤出菲律賓的蘇比克灣海軍基地與克拉克空軍基地以及2001年911事件後美國戰略重心轉移中東地區等政策,使得美軍在亞太地區失去大型基地,也沒有常駐部隊,導致美軍調度大量軍事武力的能力受限,降低在該地區的戰略影響力。儘管如此,基於對東南亞地區長期的關注程度,在重返東南亞的背景下,美國參與南海爭端,將能迅速適應形勢急遽的變化。再者,南海周邊許多東協國家,對於美國在該地區的發展表示支持與歡迎。上述兩個因素為美國在南海地區實現軍事存在的發展創造出有利之機會與條件。
The disputes of the South China Sea have gradually gotten regional states' attentions in the recent years; the situation has become internationalizd, complicated, and expanded. Due to the special strategic value, the Unite States gets involved in the area. Since the early 20th century, Southeast Asia has been the traditional sphere of influence of the Unite States. The influence began with that the Philippines was transfered to America from Spain. During the Cold War, the U.S. has many military bases and troops in Philippines and Vietnam in order to counterbalance the military expansion of the former Soviet Union. In 1973, the U.S. started withdrawal of naval and air force bases from Cam Ranh Bay in Vietnam; in 1992, the U.S. carried on the withdrawal of naval base in Subic Bay and Clark air force base. After September 11 of 2001, the center of gravity of the U.S. strategy was focused on the Mid-east region; Based on all these reasons, the U.S. military has no major bases in the Asia-Pacific region, as well as permanent troops. It reduced the power of deploying military forces and losing the influence in the region. Moreover, under the background of ”Pivot to Asia” and the long-term concern in the Southeast Asia region, if the U.S. gets involved in the disputes of South China Sea, America could rapidly response any changing circumstances. Furthermore, many ASEAN countries nearby the South China Sea welcome and support America's development in the region. The two factors above will create favorable opportunities and conditions for the military presence of the U.S. in the South China Sea.