China has around 2-3 thousand years of history in trolling its neighbors, so this is just a normal thing, they've never really been a "peaceful" country (but very few countries have). America has only been around for 2-3 hundred years? Oh, it isn't peaceful either.

You could say the same thing about China invading Vietnam because the Vietnamese overthrew their puppet Pol Pot in Cambodia, that guy said to be even worse than Batista because he literally killed a few million people. But then again, the USA and China were allies at the time (the USA tacitly supported Pol Pot as well, as the enemy of their enemy I guess).