中國若干輿論有意將南海問題提升至其「核心利益」的位階，此一提法促使美國對南海問題採取更強硬的立場，一改其過去所持的中立不介入的立場。美國強調南海問題國際化、東協和中國應簽署「南海區域行為準則」，美國並有意擔任調人。美國進而強化和越南、柬埔寨的軍事合作關係，在南海與越南舉行聯合軍事演習，美國的作法似乎正在恢復圍堵中國的戰略態勢。惟時移勢遷，美國與中國關係比以前更為密切，圍堵已無法像以前一樣有效。本來南海問題是東協和中國在角力，美國突然介入，應另有所圖。 Some of the media in China have intended to emphasize that the South China Sea is its core interest, which has prompted the United States to take a tougher stance on the issue of the South China Sea. The United States has changed its non-involvement and neutral position on this issue. It has stressed that ASEAN and China should sign a "Regional Code of Conduct for the South China Sea," and the United States intends to act as mediator. The United States has also strengthened military cooperation with Vietnam and Cambodia, and has held joint military exercises with Vietnam in the South China Sea. It seems that the United States has resumed a strategic posture in regard to the containment of China. However, since the relations between the United States and China have become closer than ever before, containment is not as effective as it was before. The tussle in the South China Sea was originally limited to ASEAN and China. However, the United States has suddenly become involved, and is expected to strategically maneuver in this area.