Nam vs China? Who you got?

Does Russia get involved?

So here is my take on all of this.

I do not think Russia gets involved. I see Russia treating this issue much the same way that China has treated the Ukraine issue.

For me, decisions in China are always reflective of the balance of power in world politics. China's maritime disputes with Japan, Vietnam, and the Philippines are foremost about projecting power. When China was weak and needed space for economic development, they did not show much interest in getting mixed up in territorial disputes (beyond Taiwan). However, as their economy and military capabilities have grown, so has China's interest in the South China Sea.

Second, this is probably about testing US commitment to the region. China wants to be the dominant player in the region and would like to sooner or later push the US out of Asia. In the short-term, I do not see war. China wants to assert itself and it wants to force Japan, Vietnam, and the Philippines into being rather risk averse over maritime disputes in the South China Sea. However, China likely wants to flex its muscles without provoking a serious conflict. Overall, China now feels it can accept some of the costs associated with acting out in the region. But I still think China wants to play it safe and avoid conflict. Especially one that would that would draw in the US.

China was more of an observer for both the French/Indochina and and the VietNam war.

A lot of that had to do with Ho Chi Minh's distrust of Mao and The former USSR's ability to supply weapons with no interest in the internal affairs within Ho's government.