Kuala Lampur, Sept. 19 -- When Philippine Defence Secretary Gilberto Teodoro Jr. announced that Britain had expressed interest in negotiating a Visiting Forces Agreement (SOVFA) with Manila, he interpreted it as a clear sign of support for the Philippines' claim in the West Philippine Sea. The symbolic weight of a letter delivered by British Defence Minister Lord Coaker - written by his superior John Healey - was not lost on Manila. It represented, in Teodoro's view, an external endorsement of sovereignty over waters that are now a flashpoint in global geopolitics.

But while security agreements proliferate, one cannot ignore the other side of the equation: trade, prosperity, and stability. The South China Sea is not only a contested secu...