2016年南海仲裁案後，南海局勢經歷了一段時間的平穩可控。但2020年是個轉折點，南海地區的形勢出現了一些新問題新情況，中美在南海的競爭對立達到了前所未有的新水平。具體而言包括：

第一，特朗普政府調整了原有的南海政策立場。7月13日，美國務卿蓬佩奧發表聲明稱，中國在南海的許多主張沒有國際法依據。這表明美國的政策立場實現了從所謂“不選邊”到公開“選邊站”的轉變，從而為美國在南海地區隨後的一系列干預行動開了綠燈。

第二，美國在南海地區的軍事介入頻率越來越高，風險性越來越大。以“航行自由行動”為例，在奧巴馬執政的八年里美軍在南海僅進行了五次，特朗普政府截止目前進行了25次，2020年截止目前進行了九次。更為嚴重的是，中美兩軍南海對峙幾成常態，2020年上半年美國在南海地區進行了超過3000架次的空中軍事行動和60餘艘次的軍艦行動。7月，美國“尼米茲”號航母戰鬥群和“里根”號航母戰鬥群在南海海域展開演習，這是美軍自2014年以來首次出動兩艘航空母艦在南海進行訓練。美國還多次派出B-1B戰略轟炸機、E-8C偵察機到南海上空，甚至多次逼近中國廣東、海南島近海，兩軍擦槍走火的風險陡增。

第三，美國對中國的指責和污名化不斷升級。奧巴馬政府時期美國對中國在南海地區的污名為“規則破壞者”，今年7月13日的聲明則首次稱中國在南海地區試圖建立一個“海洋帝國”，奉行“強權即公理”，對其他國家實施恐嚇脅迫行為。

2020年南海地區新問題新情況的出現，引發我們對中美雙邊關係的新思考。

首先，雙方的地緣政治鬥爭公開化。中美在南海地區究竟在爭什麼？近幾年美國在南海地區利益訴求由高到低的順序是：要求中國停止在南海島礁的軍事化行為；防止中國在南海建立防空識別區；維持美國在該地區的自由航行權。2020年在這些問題上雙方並未有實質性衝突，但南海形勢越來越緊張，這也反映出南海形勢具有超越具體事項的戰略意涵，變成中美競爭的地緣競技場。中方謀求南海地區的和平與穩定，而美方力圖阻止中國影響力在該地區的擴展。對美方而言，地區內國家的和平與合作將意味着中國影響力的擴大，這是美國堅決反對的，因此在很大程度上，美方是希望南海地區必須有“危機”。

其次，南海形勢由原來的小國衝鋒在前，變成了美國直接捲入。這一新特徵說明，美國具有與中國進行直接對抗的戰略決心。奧巴馬政府時期，美國支持菲律賓通過法律途徑挑戰中國的南海權利，特朗普政府時期美國在南海爭端中逐漸走上前台，對中國進行直接抗衡。

再次，軍事手段是美國對中國進行戰略對抗的可選項之一。儘管中美兩國同為核大國，爆發全面戰爭的可能性非常低，但美國在南海奉行了一種“危機邊緣政策”，對中國進行最大限度的施壓，中美南海軍事衝突的風險居高不下，隨時可能成為引爆兩國關係的“火藥桶”。

展望2021年，隨着拜登新政府上台，南海形勢的發展將呈現出一定的連續性，同時也會出現一定的調整。其連續性在於，南海將繼續是中美地緣競爭的重點區域，拜登政府在該地區的戰略目標仍將是阻止中國影響力在該地區的擴展。大國間的戰略競爭建立在軍事實力基礎之上，因此拜登政府將繼續維持在南海地區的軍事存在，“自由航行”、軍事演習、軍艦巡航、軍售貿易都將持續。

拜登政府與特朗普政府的不同之處在於實現戰略目標的手段可能有差異。拜登政府的目標或挑戰是如何在不引發軍事衝突條件下最大程度地阻止中國影響力的擴展，因此，它會在手段上進行多種務實創新，從原則上說可能包括幾個方面：

一是相對於特朗普政府的“美國模式”，拜登政府更傾向於多邊聯合，即“美國+模式”，南海地區將會出現越來越多由美國主導的多國聯合行動，包括日本、印度、澳大利亞、歐盟部分國家以及東南亞部分國家等。

二是身份政治盛行。拜登政府將繼續高舉“規則”大旗，不斷對中國進行負面建構，最終將中國貼上“帝國”、“霸權”、“非自由”、“非民主”等負面標籤，而美國在很大程度上將扮演“正義者”角色，幫助東南亞國家“維權”。

三是對中國在該地區的認同形成終極挑戰。

客觀地講，隨着中國實力的不斷提升以及中國合作外交的不斷推行，中國在該地區的崛起具有一定的歷史必然性，美國在該地區對抗中國的戰略也將困難重重，但拜登政府對中國的身份攻擊會對中國的認同形成長遠負面影響，對中國維護自身正當權益構成一大挑戰。

There was a period after the South China Sea arbitration in 2016 when the situation seemed to be stable and controllable. The year 2020, however, has been a turning point, presenting new issues. New conditions have emerged with heightened rivalry between China and the United States. Tensions have reached an unprecedented level.

1. The Trump administration has adjusted its policy stance in the South China Sea. On July 13, U.S. Secretary of State Mike Pompeo released a statement saying that many of China's South China Sea claims lack a basis in international law, indicating a turn from not taking sides to openly taking sides and giving a green light to a series of subsequent U.S. interventions in the maritime area.

2. U.S. military interventions in the South China Sea area are increasingly frequent and risky. Take the so-called freedom of navigation operations, for instance: Only five were conducted in the eight years of the Obama presidency, but the Trump administration has carried out 25 to date, nine of them so far this year.More serious, the standoff between the two militaries has pretty much become a normal state. In the first half of 2020, the U.S. carried out more than 3,000 operations of military aircraft and more than 60 operations involving ships. The USS Nimitz and USS Ronald Reagan carrier strike groups conducted drills in waters of the South China Sea in July, which was the first time since 2014 that the U.S. military had dispatched twin aircraft carriers for military exercises in the area.The U.S. has also on many occasions sent B-1B strategic bombers and E-8C spy planes to the South China Sea region, even nudging close to the airspace of Guangdong and Hainan provinces. The risk of the two militaries triggering an unintended conflict has dramatically increased.

3. U.S. finger-pointing at China continued to escalate. During the Obama presidency, the U.S. stigmatized China as a “rule saboteur” in the South China Sea region. The Trump administration's July 13, 2020, statement on the South China Sea for the first time alleged that China was attempting to build a maritime empire in the area, that it believes might makes right and that it intimidates and coerces other nations.

The emergence of these new issues and conditions in the South China Sea region prompts us to rethink China-U.S. relations.

First, the bilateral geopolitical struggle is coming out into the open. What are China and the U.S. competing for in the South China Sea? The sequence of U.S. policy goals in the South China Sea region in recent years, from high to low, is: asking China to stop militarizing South China Sea features, preventing China from establishing air defense identification zones and preserving U.S. freedom of navigation in the area.There was no substantial conflict between the two parties over such issues in 2020. But tensions are building up in the South China Sea, which shows that the situation has taken on strategic implications that transcend specific issues. It has become a geopolitical arena for China-U.S. competition.China seeks peace and stability in the South China Sea region. For the U.S., regional peace and cooperation mean the expansion of Chinese influence, which is what it resolutely opposes. Therefore, to a great extent, the U.S. side needs to foment “crises.”

Second, the South China Sea situation has evolved from its previous pattern of small countries being used as pawns and has become one of the U.S. getting directly involved. This is a new characteristic indicating that the U.S. has a strategic determination to engage in direct confrontation with China.During the Obama presidency, the U.S. supported the Philippines in challenging Chinese rights and interests in the South China Sea through legal channels. Under Donald Trump, the U.S. has gradually moved to the forefront of disputes, directly confronting China and showcasing U.S. determination to engage in strategic confrontation.

Third, military force is an option in the U.S. strategic confrontation. Although the likelihood of an all-out war between the two nuclear powers is very low, the U.S. has engaged in brinkmanship in the South China Sea and exerted maximum pressure on China. So the risk of China-U.S. military conflict in the South China Sea remains high, and could become a powder keg that blows up bilateral ties.

With the inauguration of Joe Biden as president of the United States, the South China Sea situation in 2021 will display a certain continuity, while at the same time seeing some adjustments. It will continue to be a key arena for China-U.S. geostrategic competition. The Biden administration's strategic goal in the region will remain to prevent Chinese influence from expanding.Strategic competition between major countries is always based on military strength. The Biden administration will want to preserve the U.S. military presence in the South China Sea. Freedom of navigation operations, military exercises, naval patrols and arms sales will therefore persist.

Biden may differ from Trump in his approach to achieving strategic goals. The challenge for him will be how to prevent China from expanding its influence as much as possible without triggering a military conflict. Biden will look for pragmatic innovations when it comes to approach, which in principle will include the following aspects:

• In contrast with the Trump administration's U.S.-centric model, the Biden team will likely be more in favor of multilateral collaboration — that is, a “U.S.+” model. There will be more U.S.-led allied operations featuring multiple participants, including Japan, India, Australia and some EU and ASEAN member countries.

• Identity politics will be in vogue. The Biden administration will continue to hold high the banner of “rules” while constantly framing China in a negative light and ultimately sticking negative labels onto it, such as “empire,” “hegemony,” and “non-democracy.” The U.S. will play the role of “The Just” — the one who helps Southeast Asian nations “safeguard” their rights.

• Any lukewarm identification with China by states in the region will pose a key challenge. China's rise in the region is in some ways a matter of historical necessity, and a U.S. attitude of confrontation can do harm.

Objectively, while Chinese strength is growing steadily and cooperative diplomacy is its standard practice, U.S. attacks on the Chinese character and motives could have lasting negative effects that could become a major challenge for China in building authority as a regional leader.