Interesting. China would obvioulsy not want to damage the factories and would be eager to reassure the many international clients that China was not going to "nationalize" the factories that had been built (yet).
This would get those businesses and the money grubbers who exported all our technology and jobs to Taiwan and China to pressure Washington to NOT interveine. It would probably behoove the people of Taiwan to place air defense around those factories and use them as staging grounds for counter attacks. This would FORCE the Chinese to destroy them, removing that card from China's deck.