Hypersonic missiles launched from Bejing would hit San Diego in an hour and a half.
Even assuming that their hypersonic missile were oprational and could carry a significant payload that far, that would fall under "dictator starts a war".
Why the Taiwanese have not embraced a more muscular reserve system like Norway or especially Switzerland is a mystery to me. The need to fortify their country. A good recent article on this subject: https://blogs.timesofisrael.com/chinas-three-gorges-dam-a-military-target-in-war-with-taiwan-india/