What's behind the fight is a vast quantity of oil and gas believed to lie beneath the South China Sea.
China and the other nations desperately want the energy resources beneath the South China Sea, and the dispute has caught the attention of global financial markets.
China's biggest offshore oil company, CNOOC Limited (NYSE ADR: CEO), recently updated its projection of energy assets in the South China Sea. It said the area could hold 17 billion tons of oil and 498 trillion cubic feet of natural gas.
All those resources could not be extracted, but enough could be taken out to double China's current reserves of oil and natural gas.
For its part, China's Ministry of Land and Resources says the area contains more than 40 billion tons of oil equivalent. Most of that is believed to be in the form of natural gas.
Another Chinese estimate says 2,000 trillion cubic feet of natural gas lie under the South China Sea. That would be enough gas to meet the country's needs for the next 400 years, based on 2011 consumption levels! No wonder energy-hungry China is so interested in pushing its claims in the region.
Exploration in the South China Sea has been very limited so far because few major international oil companies want to get involved in the territorial dispute. China has already successfully pressured companies like BP plc (NYSE: BP) and Exxon Mobil Corp. (NYSE: XOM) to abandon its deals with neighboring Vietnam.
CNOOC itself caused a diplomatic row with Vietnam in June when it put up for auction nine oil and gas blocks that Vietnam says are in its territory. The blocks had already been auctioned by Vietnam to companies including ExxonMobil and Russia's Gazprom.