https://edition.cnn.com/2020/09/26/asia/china-asia-territorial-claims-conflicts-explainer-intl-hnk-scli/index.html
Why does China even care about Taiwan?
Because in a totalitarian culture, where "saving face" is the highest priority, you can not have a rebellious family member declaring independence.
Especially one like Taiwan that clearly demonstrates the benefits of repudiating China's governing style and social and economic policies.
https://edition.cnn.com/2020/09/26/asia/china-asia-territorial-claims-conflicts-explainer-intl-hnk-scli/index.html
“Why does China even care about Taiwan?”
Point of pride, and a loose end after the revolution. Taiwan is where the Kuomintang government fled after the communists launched their coup. Technically, the government of Taiwan is the legitimate government for all of China. As long as they exist, the commies in Beijing have a constant reminder that they’re usurpers rather than the “people’s government”.
Why did Hitler care about Austria? Same thing.
Taiwanese are short, yellow-skinned with black hair and slanty eyes, and they talk and write Chinese. Therefore, they must be compelled to join the Master Race.
> Why does China even care about Taiwan? <
I would hazard two guesses:
1. It’s a national pride thing. And the Chinese are very big on national pride. As an analogy, suppose the Confederates still held Florida after our Civil War ended. The Federal government would resent that. Now for China/Taiwan, multiply that resentment by 10.
2. Things are looking a bit rough for China going forward. And wars are always great distractions.
When Japan defeated China in war in 1895 they got Taiwan and Korea as colonies. Japan was of course defeated. In 1949 the defeat of the restored Chinese government by the CCP meant that it and some of its supporters fled to Taiwan, and it has been governed separately (and for the last 25-30 years, freely) since.
In the meantime, the CCP bases much of its legitimacy on undoing all the colonial-era humiliations, including Taiwan. The people who live on the island don’t want to be ruled by the CCP, but that is of no concern to the CCP itself.
Why did they care about Tibet? Geopolitical hegemony.
China is essentially a country cobbled together from lesser countries. Almost every major ragion would like to break away. Weigirs, Mongolia, Taiwan...if China allowed Taiwan to walk away other would soon follow suit and the country as we know it would vanish... They see Taiwan and making an example out of it and Hong Kong as the key to the CCP strength and longevity. They will do ANYTHING to maintain that including using nukes. If the SCS falls after they have claimed it, it will be construded as a direct attack on the homeland, for which they would defend to the death. Without it, they have no way to feed itself...
They have an industrial capacity for making chips that China needs.
The same way Argentina cared about the Falkland Islands, leading to a war with the United Kingdom in 1982. It was a thorn in their minds that had to be dealt with. Not that they needed it or wanted it. Just because. China will start a world war because of having a mental fart about Taiwan, regarding the non-commie Chinese leaders there.
Sad thing is that Taiwan was an independent nation after the Japanese gave up their territorial ownership. Japan ruled Taiwan for half a century, and after WWII ceded it back to the Taiwanese. Then the non-commie Chinese Nationalists fled there and took it over. It doesn't belong to the Chinese at all, of either flavor.
The only solution I see is for Taiwan to ally with Japan, and for the Chinese Nationalists to give up rule in favor of native Taiwanese. Japan can then defend Taiwan. (Of course the Nationalists won't do this.)