Not that I want to encourage more tension, but if China can begin building structures on islands that it claims in dispute with The Philippines, then China has very little to stand on when it complains about Japan considering building on the contested islands in the East China Sea. This could backfire on China.
My feeling is that if China continues to build an artificial island and construct structures on it, the American response should be that doing so would trigger a review of US policy of not taking a position on isle ownership in territory disputes.
What chance is there of China provoking a strong response from the United States with Obama in the White House? It will be like being slapped down with a wet lettuce. China will do what it can because it knows it cam get away with it. China’s neighbors will have to act. The US will not under Obama.