China has already basically annexed Tibet. Not a lot they can do now
Would China have annexed Tibet if Tibetians could defend themselves? Not a lot they can do now? Suez, Kenya, Rhodesia, Cyprus broke the British Empire.
The US was dealing with internal unrest because of the war. I doubt China would yield to the same internal pressure
Internal unrest? Is that what brought down the helicopters at Ấp Bắc? And Khe San? Xuân Lộc? You're really committed to this "weaker is safer" theory!
Vietnam isn't literally next door to the US. Tibet shares a land border with China
Afghanistan shares a land border with the USSR.
Tibet isn't mostly jungle
Rhodesia isn't mostly jungle.
Pretty sure the Dalai Lama wouldn't support a Tibetan insurgency either
Obviously not. He ran away. So Tibet is safer from invasion, right?