Yes, I know that. I also know that it is not possible to accurately predict the state of the world in 27 years time.
I very much doubt this will cause any damage that lasts longer than 27 years. Not sure it will do any damage that lasts 27 days. Not sure it has much effect at all on anything. It's hardly the biggest bone of contention between the countries.
Do you generally think that people should be cowed into keeping quiet out of fear rather than expressing what they believe?
They can say what they like.
It is accurate to predict that in 27 years Hong Kong reverts back completely under China's control. But Hong Kong already belongs to China. Hong Kong is not independent from China. A military Chinese force is always present in Hong Kong. And China could use military force whenever it wants to stop the protests.
If China decides to use it's military force your 27 years waiting period is over. It will use the instability caused by the protests as reason to have more of a presence in Hong Kong.
You say U.S. support won't have any lasting affect or damage. You're incredibly idealistic. The U.S. response may be that which pushes China to the place where China will use their military to restore order. Then what do we do? You like to use the word 'cowed'. Do you think China will be willing to be seen as 'cowing' under U.S. pressure? Ever heard of the Bay of Pigs?
The people in Hong Kong can protest all they want. They can express what they believe all they want. They can riot all they want. They can be bold as lions and express their 'free speech' all they want. That doesn't mean the U.S. needs to get involved in their protest.
Hong Kong belongs to China.
Good-Ole-Rebel