We took enough revenge in 1967 for it. Its why you soiled your pants just thinking about intervening 4 years later while we were disintegrating another country (big ally of yours) just below the theatre in question here.
When you did put your big boy pants on 8 years after that because someone kicked out your best buddy Pol Pot back to the jungle he came from....you got your *** handed to you then as well (and no objective of withdrawal was met)....and you lost all appetite for open engagement since.
I simply ask you what you are going to do if by end of this year China does exactly 0 on the ground about dok la? Will you accept your govt talks a talk but doesnt walk the walk? A chicken dance basically.
Best part is everyone gets to see it happen in front of their eyes esp with icing on top of the chinese defence posters frustration.
Just smile and say hi like Xi Jinping ok.....instead of going WTF when you see the dissonance of reality to your fantasy like that G-20 meet.