And, sadly, like in Tienanmen Square, little would change.
The "international community" may condemn the violence and human rights abuses but, well, the "international community" still does business in Saudi Arabia, so the chance of the condemnation changing anything seems minimal.
HK-ers are alone. No one will help them.
Which probably doesn't matter one iota, given Tibet, BUT: it's going to be hard to hide that invasion from mainland Chinese who live in big cities, and may just start asking some difficult questions. If you live in Shanghai -- or I guess more to the point in Shenzen -- you'll have to work quite hard to see why you might not be next
China invading HK would certainly make peaceful reunification with Taiwan impossible though.
Did the 1st Marine Division invade LA in 1992?
Hing Kong will go back peacefully if they have the Chinese government back down. Hing Kong is also essentially a client state to a large degree. So, invasion isn’t exactly a wrong way to describe it.