What is the role of Taiwanese semiconductor industry in Chinese and American policy regarding Taiwan?

Taiwanese semiconductor industry (especially TSMC) is extremly important and valuable on the global scale. Given this:

1. Is it a major reason for Chinese interest in Taiwan?
2. Considering possible Chinese intervention in Taiwan, would getting control of the industry (or whatever would be left of it) be an important argument for the intervetion? If so, why wouldn't Taiwan commit to destory all the factories and knowledge in case China tries to occupy the island (so as to decrease the probability of intervention)?
3. Is the industry an important factor for the US to support Taiwanese independence, or they do so mostly for other reasons?

Update: I do understand that China justifies its interest with historical arguments, however countries do not always tell their real motivations, that's why I'm asking this question.