Pretty much anything that happens to abut the South China Sea.

I suppose you could also make the argument that they already did invade Tibet and Hong Kong, though that's splitting hairs.

Hong Kong was always Chinese, and was leased at gun point.

	▲	lostlogin 24 minutes ago \| parent \| next [-]
		The government that leased it couldn’t really have less to do with the government that took it over in recent times. Things got considerably worse for Hong Kong, and the citizens didn’t want to join China. It’s certainly not a given that donating it to China was the right call.
	▲	lenerdenator 5 hours ago \| parent \| prev [-]
		And now the agreement that they'd be given a more liberalistic government is being torn up at gun point.