Lowaicue
英語在香港
Xinjiang (1949), Tibet (1950-51), Vietnam, North Korea. But you are right, they have spent most of their existence violently oppressing their OWN PEOPLE so that fighting outside their borders would be too dificult.
And THAT, sir, is entirely their business.
Oh BTW Tibet should not really be on your list. I have explained it too many times to various brain deads to repeat it. Suffice it to say that you are not entirely right. (Dont believe everything Richard Gere says)
I am not sure but I think they 'supported' NK and N VN they didnt actually invade.