What you said could be true, but in this case it is not. There's a couple of things you are not seeing. What you assuming is what is happening today is what will happen tomorrow.
Being Asian, especially east Asian I thought you know enough of our culture to understand, but I could explain it to you.
China and Vietnam is currently in a deadlock over the seas, how we handle this issue is obviously going to be different than when the situation is resolved. Not even the crazy non flexible western mentality would deal with one situation the same in two different environments.
Let's look at the facts. During the Chinese civil war, Mao created a list of war criminals on the nationalists side. However, all who turned and joined the revolution on the side of the people were not only allowed to keep their positions but also promoted depending on merit. The Chinese vice premiership was even given to some one who slaughtered Communists during the purge by the nationalists early on, due to his contribution the country.
Despite all the "bad blood," China is still continue trading with Japan, Vietnam, Philippines, sure there is some boycott here and there, that happens on all sides, but the official government stance has never been one of revenge.
Lastly, the ultimate goal for China isn't Asia, it is a leader position in the WORLD, having petty conflicts and not be generous is not the Chinese ruling class' mentality since Ancient times, there has always been the carrot and the stick.
During Zheng He's voyage in Ming dynasty, he took a few kings prisoner for slaughtering his men and trying to rob him, and for fighting with him. On his return, the YongLe emperor granted them pardon and officially gave them recognition as the divine rulers of respected countries and signed trade agreements with them, as well as bestowed gifts on them.
That's the Chinese mentality, I'm not telling Philippines and Vietnam to surrender, it won't come to that, as soon as the US is gone, a mutual defence agreement and exploration agreement is more likely, China could also pump major investments into respective countries.
Working with China historically has also been one of prestige and benefit, kings and princes would kill for the privilege of presenting themselves in front of the emperor. With our return to form, our usual policy of non-interference in internal politics, no strings attached deals are far more attractive than Western counter parts, who got it into their heads that they are superior and knows best. We are not superior, but we are more numerous.
