China is withholding details on the boundaries of its vast claims to a resource-rich sea contested by five other governments because it distrusts international law and wants to ensure control over tracts of water that it considers crucial, maritime scholars say.
You have to admit that framing makes the negotiating process simple. China simply insists that other governments keep surrendering territory to China until China says that's enough.
Which fits with my past assessment of Chinese territorial claims:
I'm starting to think that an interest is "core" to China if China simply wants it.
Which is simple to remember.