對本周與奧巴馬總統的會晤成果，中國國家主席習近平和他的團隊應該感到非常滿意和寬慰。他們出入華盛頓沒有遇到任何公開的尷尬和分歧。就連總統奧巴馬、副總統拜登和國務卿克里公開提到的少數分歧，也只是順嘴而出的兩國複雜關係中正常的、需要加以調理的部分。正如奧巴馬總統在聯合記者會上說的：“我致力於擴大我們的合作，即使我們解決分歧，也是坦率而有建設性的。這就是此次訪問中，在昨晚的工作餐和今天的會晤中，習主席和我所做的事情。”這體現了奧巴馬總統的個人外交風格，因為他不是在公開場合針鋒相對而私底下又彬彬有禮的人。習近平主席公開露面的時候也莊重平和。兩人都試圖強調雙邊關係中積極的一面。

奧巴馬總統和第一夫人米歇爾在白宮設宴歡迎中國國家主席習近平訪美。

2015年9月25日，中國國家主席習近平（右二）和夫人彭麗媛（左一）在美國總統奧巴馬和第一夫人米歇爾舉行的歡迎儀式後在白宮的陽台上向大家揮手致意。

因此，從中國角度看，主要目標已經完成：大量峰會盛況的照片（有儀仗隊的歡迎儀式和精心準備的國宴）和最少的公開尷尬。習近平主席和他的代表團遇到了許多示威者，包括白宮和國務院外的示威，玫瑰園的聯合記者會自始自終都能聽到他們的抗議聲。但總體而言，媒體情況和訪問的象徵意文應該讓北京感到滿意。

實際上，這次峰會傳遞出的主要信息，是在全球治理的一系列問題上，兩個大國都在盡其所能進行合作。美中有關“全球和地區挑戰”的詳細“情況說明書”中，列舉了雙方在特定領域的合作。這在兩國元首和副總統拜登、國務卿克里的公開講話中也有明確表示。

顯然，奧巴馬政府仍強調讓中國成為全球治理合作夥伴。自從七年前開始執政，這就是他們工作要務。這也是奧巴馬2009年對中國進行國事訪問的核心目的，但是被中方拒絕了。當時，中國在多邊舞台上仍缺乏信心，它質疑美國讓中國成為“負責任的國際利益攸關方”的要求，認為那是讓中國在全球過度擴張、阻止中國崛起的另一個陰謀。

但自那以後，中國在國際上信心增強，並越來越多地在維和、公共衛生、反恐、氣候變化、核安全、打擊海盜、可持續發展、人道主義救援及其他各類全球治理活動中出力。因此，兩個大國合作的可能性增加。習近平自已發出的信息是，他更能接受中國的外交行動主義。就像奧巴馬在聯合記者會上對他說的：“習主席，我要再次感謝你對擴大我們兩國之間合作所作出的承諾。我相信這再次提醒我們，當我們努力縮小彼此的分歧時，我們就能繼續推動兩國的共同利益，這不僅利於兩國，而且造福世界。”

即使沒有G2集團，近年的全球治理合作也被證明是彌補戰略關係的粘合劑。今年夏天的戰略經濟對話同樣對全球合作寄予厚望。所以，在兩國政府喧囂不絕的分歧背後，某些穩定要素也許正在緊張關係下重新形成。

全球治理對世界和兩個大國都很重要，但它對於全面恢復困頓中的中美關係並不是萬能的。因由眾所周知，它們是現實的、深層次的，很難解決。而加以管控，防止失控行為干擾雙邊關係的其他領域，需要外交造詣。偶爾，雙方可以取得實質性進展，就像此次峰會涉及的網絡商業間諜問題，以及為避免海上或空中突發事件升級為武裝衝突，雙方構建了軍事建立信任措施。

這些敏感和困難領域取得的進展，只能通過頻繁的外交接觸才能實現，而峰會為達成共識提供了必要的機會，這是次級官員難以做到的（這也即是所謂的“加速行動型外交”）。它本身使定期舉行峰會有了充足理由。舉行峰會的另一個理由是，政府最高級別領導人直接坦率地就存在嚴重分歧的領域進行會談，可以避免問題惡化和轉移。第三個理由就是，它能最大限度地促成具體領域的實質性合作。

就這三方面來說，2015年的習奧會應該說是一次成功。地球上兩個最大國家取得了進展，建立了信任，穩定了關係。問題是，這種狀態能維持多久？過去10年的幾次峰會，都顯示了同樣的穩定作用，但僅僅只個月之後，雙方又重新開始猜疑、爭執和相互攻訐。即使無他，這也是每6個月舉行一次雙邊首腦會晤（不必是國事訪問）的強大理由。美中兩國和世界需要峰會所帶來的穩定。自從尼克松總統和毛主席1972年會面以來，中美關係史已經清楚表明，要保持兩國關係不脫軌，雙方元首必須參與、介入。

China's President Xi Jinping and his team should be very pleased—and very relieved— with the outcome of the summit meeting with President Obama this week. They got in and out of Washington without any public embarrassments or disagreements. Even the few public references to disagreements that President Obama, Vice President Biden, and Secretary of State Kerry made were contextualized as the normal part of a complex relationship that had to be managed. As President Obama noted at their joint press conference: “I'm committed to expanding our cooperation, even as we address disagreements candidly and constructively. That's what President Xi and I have done on this visit—during our working dinner last night and our meetings today.” This is a reflection of President Obama's personal diplomatic style, as he is not confrontational in public and polite in private. President Xi was also dignified and calm in all of his public appearances. Both men sought to accent the positive in the relationship.

President Barack Obama and First Lady Michelle Obama hosted a state dinner at the White House in honor of Chinese President Xi Jinping’s visit to the United States.

Chinese President Xi Jinping, second from right, and his wife Peng Liyuan, left, wave hands after US President Barack Obama and First Lady Michelle Obama hold a welcome ceremony in White House, Sept 25, 2015.[Photo/Agencies]

Thus, from the Chinese perspective, a primary goal was accomplished: lots of photos of summit pageantry (Honor Guard welcoming ceremony and elaborate state dinner) and minimal public embarrassment. President Xi and his delegation were exposed to many demonstrators—including just outside the White House and State Department and their protest were audible throughout the Rose Garden joint press conference. Overall, though, the media “optics” and symbolism of the visit should have satisfied Beijing.

Substantively, the major message conveyed by the summit was of the world's two major powers doing their best to work together on a broad menu of global governance issues. A detailed “factsheet” of US-China perspectives on “global and regional challenges” enumerated specific areas of cooperation. This was also apparent in both president's public comments, as well as those by Vice President Biden and Secretary Kerry.

Clearly, the Obama administration still places a high premium on China as a partner in global governance. This was their priority when they came into office seven years ago and was the centerpiece of Obama's own November 2009 state visit to China—only to be rebuffed by the Chinese side. At that time, China still lacked confidence in the multilateral arena and suspiciously viewed American entreaties for becoming a “responsible international stakeholder” as another plot to retard China's rise by getting it overextended in the world.

But, in the interim, China has gained more multilateral confidence and has stepped up its contributions to various global governance activities—in peacekeeping, public health, counter-terrorism, climate change, nuclear security, anti-piracy, sustainable development, humanitarian assistance and disaster relief, and other areas—and it is thus now more possible for the two powers to cooperate. Xi Jinping himself signaled a greater receptivity to China's diplomatic activism. As President Obama told him at their joint press conference: “President Xi, I want to thank you again for expanding your commitment to cooperation between our nations. I believe that it's another reminder that as we work to narrow our differences, we can continue to advance our mutual interests for the benefit not only of our two peoples, but for the benefit of the world.”

Even if it is not a G-2, global governance cooperation could prove to be the missing “glue” to the strategic relationship in recent years. This summer's Strategic and Economic Dialogue similarly placed a premium on global cooperation. So, almost by stealth and amid much clamor over the two government's many differences, perhaps some ballast is being rebuilt in the frayed relationship.

While important for the world as well as both powers, global governance cooperation is not a panacea for restoring full health to the troubled Sino-American relationship. The reasons for the troubles are well-known, they are real and run deep, and not easily resolved. Management of them—containing them from hemorrhaging into other areas of the relationship—is a diplomatic accomplishment. Occasionally—as appears to potentially be the case with the cyber corporate espionage issue at this summit—actual tangible progress can be made. Another example are military confidence building measures to avoid accidents at sea or in the air that could escalate into an armed confrontation.

Progress in sensitive and difficult areas such as these can be achieved only through intensive diplomatic engagement—and presidential summits offer the needed opportunity to forge consensus that are difficult to reach by second-level officials (this is known as “action-forcing diplomacy”). That, in itself, is sufficient reason to hold periodic presidential summits. The other reason, though, is for direct and straightforward discussions at the highest levels of government on areas of serious disagreement—lest they fester and metastasize. The third reason is to forge tangible cooperation in specific areas wherever possible.

In these three regards, the 2015 Obama-Xi Summit must be judged a success. Progress was made, trust was built, and the two great powers on the planet have stabilized their relations. The question is: how long will it last? Previous summits over the past decade have exhibited a same stabilizing pattern—only for mistrust, disagreements, and acrimony to return after a few months' passage of time. If nothing else, that is a strong rationale to hold bilateral summits (which need not be state visits) at regular six-month intervals. Both nations and the world need the stability summits provide. The history of Sino-American relations since President Nixon and Chairman Mao met back in 1972 shows clearly that presidential involvement and investment is imperative to keeping the relationship on track.