Corrik, I am (American) Chinese. Most of my family is in China. I have a family member who had a fairly high position in the government before retiring. You have no idea what you are talking about.
They said they could roll in the tanks. Why didn't they? Because it would undermine the image and world position they have worked so hard to build since Mao's death in 1976 - that of a reasonable, practical, country that is reliable and above all does not tell other countries what they can and can't do. And it would undermine foreign investment in China and trade with China.
In the earlier years (70s-90s) China was still a dirt poor country and needed foreign investment very badly. In 1984 Shenzhen (the city right across the border from Hong Kong) consisted mostly of rice paddies. Shenzhen has a higher GDP than Hong Kong today (lower per capita, but higher by virtue of greater population - though of course in the 80s HK had a way higher population too as Shenzhen didn't exist as a city yet)! My parents sent home remittances from their grad student income here in the 1980s, which is sort of unthinkable today.
So why didn't China roll tanks into Hong Kong and Macau in the 80s? Because it was not in their interest to do so. Not worth the risk when they had a vision for a much richer, greater, future. Notice that Portugal ultimately got the same result with Macau that Britain did with HK (the original lease return date was honored) without any of Thatcher's imperialist blustering.
I don't care if you negotiated the deal. You are wrong. Not going to sit here and try and leverage your genetics to act like it makes you correct. Normally colonies go to the UN and become formally sovereign nations. China refused this and said they had to come back to China as their territory. Macau was a bit different as Portugal tried to unload the colony to China multiple times and China put off taking it back over until 1999. However, it was always understood these territories would go back to China. By force if necessary as we see in regards to Hong Kong.
It has nothing to do with Taiwan, Hong Kong, and Macau considering themselves a part of China as you claim.
What? Normally colonies don't have a country to go back to. The fact that they did here is exactly my point. ---
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