China should seriously warn Japan that their unreasonable seizure of the Fisher Island would bring them a national diaster.
Also, China should prepare a force large enough to strike an overall annihilation of the enemy by conventional or unconventional weapons.
Russian had warn Japan with that tone, and ever since, Japan doesn't even dare to challenge Russia anymore.

I think China has that ability too. The problem for China is that their present leaders are "politicians" rather than revolutionists or patriots.

China should really change its "No First Use of Neclear Weapon Policy" in order to deter outside invasions. Only if China can resort to Nuke weapon, China can block both Japan and its supporting country behind.