Adam Minter writes for Bloomberg View about the roots of Beijing's negative attitude toward Hong Kong. He trots out the usual suspects: Westernized attitudes and expectations, distain of "mainlanders" from the rest of China, and the often-forgotten fact that many of today's Hong Kong residents, or their parents, escaped Chinese terror campaigns and privations by fleeing to HK.
This last one Minter brushes past too quickly, I believe. Possibly as many as half of the population of modern Hong Kong are in fact refugees from Mao's China, fleeing the hunger, the insanity of the Great Leap Forward and the Red Guard teenage hoodlums.
During the Mao period the border around Hong Kong could have been mistaken for the Berlin wall - fortified and guarded. Many refugees arrived by sea, slipping past Mao's patrol boats disguised as fishing folk.
Everyone who escaped repudiated Beijing's leadership-of-the-moment by their actions. For Beijing to view Hong Kong residents today as loyal, patriotic Chinese would require somewhat improbable forgiving and forgetting.