Understanding the Freedom of Navigation Doctrine and China-U.S. Relations in the South China Sea

The South China Sea has evolved from a territorial and maritime dispute between China (including Taiwan) and the other four claimant states, to a show of force primarily featuring the United States, as a strong maritime power and a user State of the South China Sea, and China, as a growing regional maritime power struggling to pursue its maritime interests as a coastal State. China and the United States, both having legitimate interests in the South China Sea, have divergent views on several issues: freedom of navigation, state practice of international law, and approaches to maritime dispute management and etc.

The patrols performed by the US navy vessels Lassen, Curtis Wilbur, and William P. Lawrence stem from the US policy of asserting freedom of navigation in the South China Sea. Both China and the United States view freedom of navigation as vital to their national interests, but differ in defining the proper exercise of that freedom in at least two ways. First, they disagree on whether certain types of military activities in coastal States’ Exclusive Economic Zones (EEZs) fall within the scope of freedom of navigation. The categories of military activities which have proven controversial include those that will potentially impact the marine environment and those which could be categorized as marine scientific research and require prior permission from coastal States. Second, while China and the United States do not contest the existence of a right of ‘innocent passage’ in territorial seas under the 1982 United Nations Conventions on the Law of the Sea (UNCLOS), they differ on the specific rights of ‘warships.’ The United States believes that warships enjoy the same right to innocent passage as commercial vessels, while China mandates in its domestic law that flag states of warships exercising innocent passage must obtain prior permission from coastal States.

This report outlines the perspectives of the US and China in the South China Sea dispute including their divergent legal interpretation on navigation regime associated with the concept of freedom of navigation, and discusses the relationship between military activity and freedom of navigation. The debate on the legitimacy of military activities in a foreign country’s EEZ reflects the competing interests of two groups, the user States and the coastal States inspired by the doctrine of Mare Liberum and Mare Clausum respectively. The report looks into the role of the third party compulsory dispute settlement mechanism of UNCLOS in addressing these divergences. The report also discusses the efforts in bridging the conceptual and perception gap from both the academic and policy perspectives.

Despite the divergent legal interpretations and perception gap, the United States and China have shown the political willingness to keep the South China Sea dispute under control and to enhance maritime cooperation. Whether this balance might continue during the Trump administration is not yet clear. Both the United States and China should endeavor to avoid escalation stemming from confrontations or tensions triggered by frequent US freedom of navigation operations or the Chinese construction of military facilities on the reclaimed features in the Spratly Islands. China and the United States share interests in maintaining peace and stability in this region and should further enhance maritime cooperation on nontraditional security.