All the more reason for Obama to take firm action here, rather than look like a paper tiger. Really, all this would take is moving a carrier to the area or a squadron of F-22s to Guam. That's it. China won't start a war over this, that's not their recent pattern. Even Clinton had the foreign policy smarts to move carriers into the region when China got too big for their britches (Taiwan, 1996). If Obama doesn't respond with some sort of response, then all his good work in the region would be seriously undermined.