What can you do about this? Pretty much nothing. China is the second largest economy in the world, and has the second most powerful military. In addition, what they view as the integrity of China is one of their biggest priorities. In addition, they have always viewed British control of Hong Kong as a national humiliation and are bent on erasing all traces of that memory. The way it stands right now, China can inflic…
That assumes that the rest of the world would be using Chinese aggression on Hong Kong (and Tibet, and the Uighur peoples, and...) as the sum total of their motive for any reaction.
If, instead, these actions are just seen as a moral justification behind a very different motive (e.g. destroying the CCP and giving control of the Chinese mainland back to the Taiwanese CNP, where foreign powers would have already made deals with the CNP from a position of strength that would give great economic advantages; or even an imperialist land-grab that sees China parted up as colonies of these foreign powers) then the “trigger event” doesn’t have to weigh very heavily on the scales at all. WWI was started under similar pretences.
> If Great Britain, and the rest of the world did not have the will to resist China taking control of Hong Kong in 1985 and 1997 when China was a lot less powerful, a lot less developed, and a lot more susceptible to pressure from the rest of the world, there is no hope for now.
Another way to think about this, though, is that multilateral cooperation gets easier as external pressure increases. It’s hard to get a coalition of countries together to fight a China that isn’t a threat; and without that coalition, you’ll be considered an invader (like Russia in the Ukraine, or the US in Vietnam) rather than a rescuer (like the US in some other countries.) This means that, even in a situation where every country individually would like to put a stop to what China is doing, the Nash equilibrium on a global-political level is for each country to do nothing until China (or whoever) gets really bad, and only then, suddenly, will everyone cooperate to fight them.
(Though, also, on a more cynical note, a more developed—but not yet fully urbanized—country, is a more valuable country to annex. One could view this period where China was allowed to develop as a farmer allowing a crop to “ripen.”)