The need for a uniform understanding of international norms regarding freedom of navigation is increasingly important as more States develop capacity to act in the international maritime realm. Nowhere is the issue of freedom of navigation more contentious, with more potential to spark wider conflict, than in the South China Sea (SCS). Both the United States and China profess an interest in the free navigation of commercial vessels in the region. Beyond commercial shipping, however, the two nations disagree on the important issue of freedom of navigation for military vessels. The United States believes all nations have wide latitude under international law to conduct military activities at sea. China argues that U.S. military activities in the SCS infringe on Chinese sovereignty. The resolution of this dispute, which has resulted in several confrontations at sea between the two nations, has implications for peace and security in the SCS and beyond.