We do know well about mentality of Chinese, you would like to be master here and dominate Asia. It is true ambition of Chinese. Expansion policy doesn't help you. In fact China has denied follow negotiation with Vietnam over Paracel and with other partner who is related to spratly.
Xisha is an inherent territory of China with islands are in full development that has cost billions of dollars. They are beyond to be negotiated, I am afraid. Do not be over optimistic; even one on one talks on Nansha would not involve giving up on historic rights and entitlements of China.
Bilateral talks mean upgrading the status quo and managing the disputes with no major incidents among the related parties.
Occupation illegally on such man made islands is meaningless for China security, when American has right to take care for free navigation and Aviation on East and South East Asia.
If those full-fledged islands can be developed as defensive structures, they do provide some deterrence to the US military adventures. As China is more involved in ensuring freedom of navigation in SCS, the US will be squeezed out. But, obviously, for some time to come, China and the US will share high waters as China goes further blue navy. Nonetheless, freedom of navigation and China's ownership of islands in SCS are two different things. China will slowly absorb the islands, while at the same time, reinforcing freedom of navigation, which will keep the US with no real excuse to intervene.
In the final analysis, if it intervenes militarily, damaging China's interests in any way, it will be responded equally. If they are ready to die for you and the Philippines, we will help them achieve the objective.
What China has softly handling with VCP recently is tactic of China in this moment only. True intention of China to swallow Islands of Vietnam in East Sea of Vietnam, is unchanged.
Definitely, those islands will eventually be taken back. But we will recognize your rights for freedom of navigation and ocean exploitation.
USA and Japan will be present on East Sea of Vietnam to keep China under controls. It is no bad for Vietnam.
Japan is fine as we are readying to sign world's third largest free trade regime.
You can invite the US to stay nearby, but do not give them any base rights that would allows soldiers to be stationed. That's not healthy for your nation's moral and cultural viability.
As I see you are smart as it is now the Philippines that takes all the brunt while Vietnam enjoys positive externalities only.