Modern "nation state" is a western concept gradually developed after WWI. China's concept of sovereignty defined by boarders was developed during Southern Song Dynasty when it was forced to negotiate with Jin to delineate a borderline. Previously, Chinese dynasties had no concept of boarders, but viewed the whole world "tian xia" like an egg, with center as Hua xia that can be expanded into outlaying barbarian lands.
Of course, China is no longer traditional China especially after full contact with the West and has completely accepted modern concept of "nation state" and respect for sovereignty.
We have to acknowledge that almost all modern political concepts are defined by the Europeans, even communism, let alone today's world order. Ironically, you are here upholding modern nation state to counter the west.
China is not powerful enough to rearrange today's world order so the best for China to do is to work with the west to its own advantage. I don't know why some Chinese members here belittle Japan. Japan was very successful to utilize the West's support during cold war against China and became extremely developed country. Japan at least has developed its unique modern political system and cultures that are attractive to others. China has long way to go. It just makes me sad that China is no longer a splendid civilization that others esteem.
