USA is forcing China to take Taiwan by force.

http://www.chinapost.com.tw/taiwan/national/national-news/2017/07/13/499383/aits-chairman.htm

The USA mooted the idea of performing navy port of call in Taiwan and passed a provision last month.  Thereafter, the USA upped its ante by trying to make it a legislation for its navy to establish the port of call in Taiwan.

http://timesofindia.indiatimes.com/world/china/china-slams-us-defence-bill-over-taiwan-provision/articleshow/59633295.cms

This is against the one China policy and anti secession law in China.  If China doesn't invoke its anti secession law after USA port of call in Taiwan, the Chinese won't trust the communist party anymore.  Therefore, China has to take Taiwan by force to satisfy its nationalistic sentiment.

I don't understand how the USA congress can have the power to intrude and contravene another sovereignty.  If this practice is allowed in the international arena, any country can do the same and China can also pass a legislation in its parliament to violate the sovereign of USA.  Even ICJ which is under UN cannot accept and rule on any case that will violate another sovereignty.