China has some 18 long-range single war head ballistic missiles built during the 1960's. The U.S. has thousands of multiple warhead missiles including many on subs and carriers off China's coasts. For Washington it's easier to go to war than to cut taxes. China has virtually no amphibious forces able to attack Taiwan.
China benefits greatly from trade and know how from Taiwan .
China has no interest in destroying Taiwan. They wouldn't invest if there were not property rights and personal safety for most. Many Taiwanese even retire to China. Hong Kong is still free and rated No. 1 in the Heritage Foundation Index of Economic Indicators . The Falun Gong, outlawed in China, are legal in Hong Kong.