The US defence department has yet to release its annual freedom of navigation report for the 2019 financial year. While there is no fixed time frame, the reports for 2017 and 2018 were released on December 31 of those respective years. In 2018, the United States carried out seven freedom of navigation operations against China. For 2019, there will be no fewer, for sure, given the growing chorus of military and civilian leaders who have voiced their support for such operations against China. Of the US’ freedom of navigation operations in 2018, one that is particularly noteworthy was conducted on September 30 by the destroyer USS Decatur, which had a close encounter with a Chinese vessel that led to a near-collision.With more frequent freedom of navigation patrols, the cat-and-mouse game between the US and Chinese navies is more likely to lead to misunderstanding, miscalculation or real conflict. Notwithstanding the strategic and geopolitical competition between China and the US——which is the essence of the SCS issue, such operational confrontations are a reflection, more or less, of different understandings and interpretations of the applicable rules in international law. The US carries out freedom of navigation operations on the basis that it needs to challenge the states making “excessive maritime claims”. This argument raises several questions. First, is there a neutral judge who can decide whether a maritime claim is excessive or not? The fact is that the US alone act as the judge, makes the decision and conducts freedom of navigation operations accordingly. Second, what is the benchmark used to determine the excessiveness of a maritime claim? Ideally, it should be the rules of international law, as generally accepted by the international community, such as the United Nations Convention on the Law of the Sea (UNCLOS). Not being a signatory to the 1982 UNCLOS, the US instead makes its own judgments according to its own unilateral understanding and interpretation of the rules. This often gives rise to cases of American international law versus international international law. And the more the US withdraws from multilateral and bilateral treaties, such as the Paris climate agreement and the Intermediate-Range Nuclear Forces Treaty, the deeper the conflict between the two versions of international law. The most contentious issue relates to the freedom of innocent passage for foreign warships in territorial seas. The core issue is whether warships enjoy the same right of innocent passage as merchant ships, without prior notification or authorisation. Both the 1958 Geneva Convention and UNCLOS have intentionally maintained ambiguity about this matter, as has been acknowledged by many Western experts. Despite this deliberate ambiguity in the treaty, the US insists that all the provisions in UNCLOS, except for those that limit seabed mining, reflect customary international law. While this argument gives the US leeway to pick and choose rules to its advantage, it has no support in practice. According to the database of the UN Division for Ocean Affairs and the Law of the Sea, 49 of all maritime states have enacted national legislation restricting the innocent passage of warships; nine of these countries are in Asia, including China, India, Vietnam and South Korea. The number – 49 – is telling in itself Elihu Root, who served as US secretary of state under President Theodore Roosevelt, represented the US in the North Atlantic Coast Fisheries case. He said: “Warships may not pass without consent into this zone because they threaten. Merchant ships may pass and repass because they do not threaten.” The US also accuses China of impeding freedom of navigation in the South China Sea. Yet, the fact is that there has been no report of any impeding of merchant ships in the region. Seaborne trade via the South China Sea has been in no way affected. Once again, a small, but effective, trick is being played to deliberately conflate the rules of military and commercial navigation, whether in the official US line or media reports. Finally, when the US decides that other countries’ maritime claims are excessive by its own standards and maritime disputes then arise, how should those disputes be settled? Given that disputes among states have often led to wars, the UN Charter clearly provides that “… all Members shall settle their international disputes by peaceful means …” and “… all members shall refrain in their international relations from the threat or use of force”. However, since 1949, the US has been the only state which, through its freedom of navigation operations as a state policy, applies military force to settle disputes. To sum up, conflict prevention in the South China Sea depends on the US abiding by generally accepted international rules instead of its unilaterally interpreted American rules. Peace and stability in the South China Sea depends on the US seeking peaceful means to settle maritime disputes instead of resorting to military force to enforce its unilateral interpretation of the rules. Capt. (Retd) Tian Shichen, a senior research fellow, is Vice President of the Grandview Institution and Director of the Center for International Law of Military Operations. He is also a PhD candidate in Wuhan University. The views and opinions expressed in the article are those of his own and do not necessarily reflect the official policy or position of any agency of the Chinese government.