China has been expanding its frontiers ever since it came under communist rule in 1949. Yet no country dared to haul it before an international tribunal till the Philippines in 2013 invoked the dispute-settlement mechanism of the United Nations Convention on the Law of the Sea (UNCLOS), setting in motion the arbitration proceedings that this week resulted in the rebuke of China's claims in the South China Sea.

The trigger for Manila approaching the International Tribunal for the Law of the Sea (ITLOS) was China's capture in 2012 of Scarborough Shoal, located close to the Philippines but hundreds of miles from China's coast. ITLOS then set up a five-member tribunal under The Hague-based Permanent Court of Arbitration (PCA) to hear the case. Beijing tried unsuccessfully to persuade the tribunal that it had no jurisdiction to hear the case. Last October, the tribunal said that it was "properly constituted" under UNCLOS, that the Philippines was within its rights in filing the case, and that China's nonparticipation in the proceedings was immaterial.

Now in its final verdict delivered unanimously, the tribunal has dismissed Beijing's claim that it has historic rights to much of the South China Sea and ruled that China was in violation of international law on multiple counts, including damaging the marine environment through its island-building spree and interfering with the rights of others. The panel effectively declared as illegitimate China's South China Sea boundary (the so-called nine-dash line).