Yes I know. Yes it was extortion, not exactly a new technique in international diplomacy.
Before we get too high up on the moral horse about this we should remember how the British presence in Hong Kong got started. Started to sell opium in China against the wishes of the Imperial government. And yes I know the British tried to sell European manufactured goods there. However there was no market for them, only a market for opium. The British fought a war with the Chinese to keep that market open. The Chinese haven’t forgotten. Imagine if the South American drug cartels fought us to keep their market open. ( Actually they are, though it may be more a political & propaganda war then shooting. I guess we’ll see who will win in the end.) Acquiring HK is their revenge, the happiness or not happiness of the locals don’t mean a thing in the Imperial\Communist scheme of things.
Gosh. "Imagine" that.