Territory - Spratly Islands

When too many things are labelled "core interest", it's no longer a core, but more properly a ... bundle! Chinese officials reportedly told the US that they considered the South China Sea as part of China's "core interest" of sovereignty. This would add to the list of Taiwan, Tibet and Xinjiang, issues on which China would persistently refuse to give any concession. But this would make no sense at all, since territorial sovereignty over the islands on the South China Sea is disputed among multiple states and China's claim to them is much weaker, legally and politically, than those to other "core interest" areas.