[Divemaster]

Here's my take:

China has said in the past that if we recognize Taiwan as a nation, China will invade Taiwan. Officially, they consider Taiwan as a renegade Chinese province.

Except for once (a slip up), no American president has said what the U.S. response to an invasion would be. Saying we will defend Taiwan is a line in the sand that forces action. Saying we will not defend signs Taiwan's death warrant. Yet, we sell Taiwan $$ billions in military hardware each year for their own defense. Taiwan wouldn't stand a chance alone against the PLA naval, air, and land forces. Losing Taiwan would be a huge blow to U.S. prestige and influence in the Pacific, and globally.

China sees Trump's call as a dangerous step towards U.S. recognition of Taiwan as an independent nation.

China getting their collective panties in a wad over that phone call is a sign of them trying to project power regionally, yet they don't know how to read PEOTUS Trump and are worried about the future of US-China relations.

China plays a multi-decade political game while the U.S. plays four years at a time, yet our China policy, vis-à-vis Taiwan, has remained fairly constant since the early 1970s.

China is confused for the moment and will, in spite of complaining, will probably take a near term wait and see attitude until they figure out what the new China policy will be.