This is common knowledge available anywhere.

https://en.wikipedia.org/wiki/Taiwan

https://en.wikipedia.org/wiki/History_of_Taiwan_(1945%E2%80%93present)

https://en.wikipedia.org/wiki/Chinese_Civil_War

Those all have sources. There are also lots of reputable YouTubers with relevant academic credentials that have coved this, Asianometry and William C Fox are two that I recall covering the subject. I think Caspian Report did as well at one point in the last few years. This is like ultra basic surface level stuff everyone should know or severely question their sources and echo chambers if they are not made aware of this fundamental information.

Why is there any mystery here. They said they intend on ending their civil war and have shown no indication whatsoever that such a statement is only rhetorical or posturing. Taiwan has never tried to be independent of China. It still claims sovereignty over all of China.

If the US Confederates had retreated to Cuba and others had intervened on their behalf, while the Confederates still claimed dominion over a part of the USA, you can bet your ass the US would invade Cuba as soon as they had the opportunity. We can all decry the whole thing, but it is their conflict. If anything, we should be evacuating anyone and anything that needs to leave and capitulating without further involvement. Like if your neighbor and their spouse are arguing, stay out of it for the benefit of everyone. This is not some mate getting abused that needs help. This involves two bloody parties where all sides have done monstrous things and that needs to get resolved one way or another. Both can't claim dominion over all. The past cannot be bowdlerized for convenience or exploitation for profit of western criminal capitalist abuse. No one needs to fight or die, but a resolution must be found.