Key point: China is rushing ahead with preparations to ensure it would gain the upper hand in any armed conflict over its territorial claims.

Last year China’s defense minister, General Chang Wanquan, implored the nation to ready itself for a “people’s war at sea.” The purpose of such a campaign? To “safeguard sovereignty” after an adverse ruling from the International Tribunal for the Law of the Sea. The tribunal upheld the plain meaning of the UN Convention on the Law of the Sea (UNCLOS), ruling that Beijing’s claims to “indisputable sovereignty” spanning some 80-90 percent of the South China Sea are bunk.

A strong coastal state, in other words, cannot simply wrest away the high seas or waters allocated to weaker neighbors and make them its own.

Or, at any rate, it can’t do so lawfully. It could conceivably do so through conquest, enforced afterward by a constant military presence. Defenders of freedom of the sea, consequently, must heed General Chang’s entreaty.
Southeast Asians and their external allies must take such statements seriously—devoting ample forethought to the prospect of marine combat in the South China Sea.

That’s the first point about a people’s war at sea. A clash of arms is possible. Statesmen and commanders in places like Manila, Hanoi, and Washington must no
discount Chang’s words as mere bluster.

Indeed, it’s doubtful China could comply with the UNCLOS tribunal’s ruling at this stage, even if the Chinese Communist Party leadership wished to. Think about the image compliance would project at home. For two decades now, Beijing has invested lavishly in a great navy, and backed that navy up with shore-based firepower in the form of combat aircraft, anti-ship missile batteries, and short-range warships such as fast patrol craft and diesel submarines.

https://news.yahoo.com/inside-chinas-peoples-war-plan-013000459.html