在中美所有关系当中，军事关系是最困难的。二十多年来，两个大国在其他领域的关系起起伏伏，而防务关系的模式却局限在“开和关”上。缺乏理解和根深蒂固的怀疑使两军关系始终处在低水平，且异常脆弱。不过近年出现了积极动向，值双边关系总体下滑之际，一些观察家甚至称赞两军关系是亮点。看来，中美军事关系已经进入一个“新常态”，它取得的进展令人鼓舞，同时挑战也相当严峻。

衡水巡防舰随一艘阿利·伯克级驱逐舰和一艘高邮湖补给舰驶往夏威夷参加2016 RIMPAC环太平洋军演。

这个“新常态”下的一个积极进展是近来两军关系出现弹性。双方的谅解就是，两军关系如此重要，即使困难当头，也必须保持。而今，中国人民解放军和美军的互动频率与密度加大。中国海军参加美国太平洋舰队主导的“2016环太平洋军事演习”，以及海军作战部长约翰·理查森上将、太平洋舰队司令斯科特·斯威夫特上将、陆军参谋长马克·米雷将军相继访华，就是两国因南海和“萨德”部署互斥之际仍保持沟通与交流畅通的实例。高层访问不仅次数频繁，也开诚布公、畅所欲言。

“新常态”的特点还在于机制性交流与对话的扩大与深化。两军每年举行的“国防部防务磋商”和“国防部工作会晤”更具互动性、建设性，而双方旨在避免海空意外相遇的“海上军事安全磋商”机制已经取得具体成果。在国家层面，两国国防官员都参加了“战略安全对话”。两军还致力于在战略规划部门、不同军种等对口防务领域之间建立新的对话平台。

功能性交流构成两国军事关系的实质，其中包括军事院校的互访、学术交流——比如中国军事科学院和美国陆军战争学院联合主办国际问题研讨会、军事医疗单位和反恐机构间的交流、美国二战期间失踪人员遗骸定位备案合作、舰船互访等。近年双方的联合演习也多于以往，如在亚丁湾举行的打击海盗联合演习、在中国和美国举行的人道主义救援减灾演习，舰船到访期间举行的搜救演习。功能性交流是建立信任和培养合作习惯的重要途径，两军每年开展的交流项目已超过50个。

2014中美海军舰艇在亚丁湾举行联合反海盗演练（选自：新华网）

“新常态”中另一个值得注意的新发展，是两军之间有关预防管理危机的措施与机制。2014年底，中美两国国防部达成两个谅解备忘录，一个是关于重大军事行动通报，另一个是关于海空相遇安全行为准则。去年晚些时候，两个谅解备忘录又加进了“使用国防部直通电话的军事危机通报机制”附件，以及相遇准则中有关空中相遇的部分。如今，危机预防管理和增进互信措施是两军关系中重要的新要素，双方越来越频繁地与对方相遇，而即使在最坏情况下，它们也是至关重要的稳定器。

况且，中美军事关系已超越传统两国边界，走向地区乃至全球领域。随着中国军事影响力扩大到全球，它发现自己有更多机会与美国对手合作。譬如，在东盟防长扩大会议框架下举行的人道主义救援减灾、军事医学、搜救、反恐等联合演习中，中美军队都发挥了主要的支援作用。中美海军巡逻舰每年在亚丁湾进行联合演练。中国海军舰艇与俄罗斯、美国、挪威军舰共同执行了联合国销毁叙利亚化学武器的任务。尽管多边框架下的军事合作仍在起步阶段，但它预示着一个“新常态”，即中美两军将有更多共同利益，并将承担更多共同责任。

然而，这个“新常态”也有消极一面。中国与邻国（其中一些是美国盟友）的双边纠纷给两军带来新的摩擦，引发了严重多边和地区后果。对中国来说，领土主权是最重要的国家利益。而对美国来说，对盟友的防务承诺是其地区安全架构的关键。当前美国的军事动向，包括在西太平洋部署最先进武器装备、增加未来的军事存在、举行盟国间大规模军演、在南海实施“航行自由行动”、实施新的防务安排如在菲律宾轮流部署军事基地、升级与日本的安保条约、向中国的邻国出售武器、决定在韩国部署“萨德”系统等，所有这些，都让中国感到美国是在利用其同盟框架抑制中国的尤其是军事上的崛起。这已经被证明是继续增进两国军事关系的一个主要障碍。

归根到底，当前中美防务关系比以往更有弹性，更具实质性，也更加广泛。但要让它始终行驶在积极的轨道上，仍有大量工作要做。

Of all relationships between China and the United States, the military one had been the most difficult. For more than two decades, while relations between the two great powers in other fields had gone through ups and downs, defense relations have been trapped in an on-and-off pattern. Lack of understanding and deep-rooted suspicion had kept military ties at a low level and rendered them highly vulnerable. However, recent years have witnessed more positive developments, and some observers have even cheered the military relation as a highlight in a generally downhill bilateral relationship. It seems that the China-US military relationship has entered a state of “new normal”, in which progress is encouraging, though challenges are daunting.

The Hengshui frigates sails behind an Arleigh Burke class destroyer and the Gaoyouhu supply ship, all on their way to Hawaii in the RIMPAC 2016 Exercise.

One positive development in this “new normal” pattern is the newly found resilience in the mil-mil relation. The mutual understanding is that military ties are so important that they have to be maintained even in difficult times. The Chinese PLA and the US military are now interacting with each other with more frequency and greater density. The Chinese navy's participation in the RIMPAC 2016 Exercise hosted by US Pacific Fleet, and the consecutive visits to China by Adm. John Richardson, Chief of Naval Operations, Adm. Scott Swift, Pacific Fleet Commander, and Gen. Mark A. Milley, Chief of the Army Staff, are examples of unimpeded communication and exchanges at times when the two countries are pointing fingers at each other in the South China Sea and on the THAAD deployment decision. High-level visits have not only been frequent in number but also candid and communicative in style.

The “New Normal” also features the extension and deepening of institutionalized exchanges and dialogues. Annual Defense Consultative Talks (DCT) and Defense Policy Coordination Talks (DPCT) between the two military establishments have been carried on in a more interactive and constructive way. The mechanism of the Maritime Management Consultation Agreement (MMCA), in which both sides have tried to work out ways to avoid accidents at sea and in the air, has yielded concrete results. At the national level, defense officials on both sides have participated in the Strategic and Security Dialogue. And the two militaries have worked to set up new dialogue platforms between defense counterparts, such as between the strategic planning organizations and the services.

Functional exchanges make up the substance of the military relations, including reciprocal visits by military academies and schools, academic exchanges such as a seminar on international issues jointly sponsored by the Chinese Academy of Military Science and the US Army War College, the exchange between military medical units, counter-terrorism units, cooperation of archivists to locate the remains of US MIAs during the Second World War, and port calls. Recent years have seen more joint exercises than ever before, such as a counter-piracy joint exercise in the Gulf of Aden, HADR (humanitarian assistance and disaster relief) exercises in both China and the US, and SAR (search and rescue) exercises in conjunction with port visits. Functional exchanges are the essential way to build trust and develop the habit of cooperation. The two militaries carry out more than 50 exchange programs every year.

Chinese and American navy vessels were on joint Anti-piracy Drill in the Gulf of Aden in 2014（Source:Xinhuanet)

Another new development worth noting in this “New Normal” are the measures and mechanisms to prevent and manage crisis between the two militaries. At the end of 2014, the US Department of Defense and Chinese Ministry of National Defense agreed upon two MOUs (Memorandum of Understanding), one on notification of major military activities, another on rules of behavior for safety in air and maritime encounters. Later last year, an annex of “military crisis notification mechanism for use of the defense telephone link” and an air-to-air part of the rules of encounters have been added to the two MOUs. Crisis-prevention management and confidence building measures are important new elements in the relation now that both militaries find themselves come across each other frequently. They are crucial stabilizers even in the worst circumstances.

In addition, the China-US military relationship goes beyond its traditional bilateral boundary, and moves into regional and even global arenas. With the Chinese military extending its global reach, it finds more occasions to cooperate with its US counterpart. For example, both militaries take a major supporting role in the ADMM+ framework joint exercises on HADR, MM, SAR, counter-terror, and so on. Chinese and American naval patrolling ships carry out joint drills each year in the Gulf of Aden. The Chinese naval vessels, together with Russian, American and Norwegian vessels, have jointly accomplished the UN mission to destroy chemical weapons from Syria. Even though military cooperation in a multilateral framework is still nascent, it foreshadows a “New Normal” where the two militaries may have more common interests and share more common responsibilities.

However, the “New Normal” pattern has a negative side too. China's bilateral disputes with its neighbors, some of whom are US allies, have brought the two militaries to new frictions, triggering significant multilateral and regional ramifications. For China, territory is the vital national interest, and for the US, the credibility of its defense commitment to allies is key to its regional security architecture. The current US military development, including deployment of the most advanced weaponry to the Westerm Pacific, increase of forward military presence, large-scale allied exercises, FONOPs in the South China Sea, new defense arrangements such as the rotational deployment to the military bases in the Philippines, upgrading of the security treaty with Japan, arms sales to China's neighbors, and the decision to deploy a THAAD system in the ROK, all give China the impression that the US is using its alliance framework to suppress China's rise, especially in the military dimension. This has proven to be a major obstacle to further improvement of the military relation.

To sum up, the current China-US defense relationship is more resilient, substantive, and extensive than before. However, to keep it on a positive track, there is much to be done.