The difference between now and 1989 is
that the US has a POTUS who won’t stand idly by
and let the ChiComs run over their own people with tanks
in the name of preserving cheap labor.
I agree he won’t ignore what happens there, but no president, not even Reagan back in his day, would be able to reverse China’s military takeover of Hong Kong, if China chose to do so.
Trump will hit them in other ways...economic, maybe military action in some other area, maybe giving/selling some serious hardware to Taiwan. So, yes, it will be interesting.
That, and the fact that it will be far more difficult for the ChiComs to control the images, videos and live streams coming out of HK to the point where even the Europeans might actually stand up straight and take notice.