Hutch and Cleon seem to have a few more brains than most McCarthy-wanabees posting here.
Some thoughts. I'm not addressing the right or wrong of the Tiawan issue, just trying to show a different perspective as best I can. Take them or leave them.
The part of China I'm living in has been Mongolian, Russian, British, American, Japanese and Korean at some time in the past. With a few exceptions, within living memory. That says a lot about Chinese "expansionism".
I suspect that some here would not bat an eyelid if America, Britain, Japan or even Russia said they wanted it back under their control.
Tibet once had control of most of southern China. Is it all Tibetan territory or is it Chinese?
Here the China-Tiawan issue is considered a Chinese-Tiawan problem and from almost any practical sense, historically, economically and politically should be left to China and Taiwan without others poking their noses in causing more problems than they solve.
Most Chinese enjoy Japan telling them what to do about what is considered part of their country about as much as Americans would enjoy France telling them what to do with, say, Alaska. Even though France hasn't raped, tortured, murdered, imprisoned or experimented on too many Americans in the last two thousand years.
I say all this to try to add some perspective and a small insight into Chinese thinking, from a country where the last 5,000 years of history is actually important to most of the population and it doesn't get ignored just because is doesn't fit comfortably with Japan or fickle America for this current tick of the clock.
The cold war is over...for those of you that have yet to notice. Chairman Mao is still dead and as I have become tired of repeating, judging modern China by the politics of the 50's, 60's and 70's makes as much sense as doing the same for America.
IMHO if Taiwan just kept quiet and concentrated on trade instead of creating a big fuss when their strings are pulled by Japan/American, the "issue" would be quietly ignored and arbitrary lines on maps would not be an issue. As an example, there are several lines on maps that are "in dispute" between China and Russia, China and India, China and [pick a country close by] but we hear little about them as it is economically practical for both sides to 'quietly ignore' them.
My fear is that this constant prattle may cause China to make a stand on all disputed (some rightly, some wrongly) lines on the map. I fail to see how anybody, least of all Americans, would benefit from a destabilisation of the entire area. Have a look on the map and see what fun it would be when you include India and Russia (yes, they have territory "in dispute").
With such a long history, it is very hard to argue one way or another for any one territory. Parts of Europe and the middle-east have been Chinese. Who is the legitimate "owner" of Macau? Should Normandy be British? Almost any claim of territory can legitimately be claimed by one side or the other and as far as time of occupation is concerned, Taiwan comes a long way down the list and as, in Chinese eyes, it was occupied by a foreign power's runaway puppet, even less so.
China-Tiawan is a political and economic issue. I am curious as to why America/Japan wish to turn it into a war-zone? Will America's big successes with warfare in Korea and Vietnam prove invaluable against a country a little bit bigger?
Curiously, If I ask Chinese "Do you believe that Hong Kong would be back with China if it had been American before?" They answer "No!".