How do US arms sales to Taiwan work and why are they such a sore point for China?

After US President Donald Trump’s summit with Chinese leader Xi Jinping earlier this month, much focus has been put on Washington’s support for Taiwan and US arms sales to its government.
The New York Times

After Months of Arguing, Taiwan Lawmakers Approve $25 Billion for U.S. Arms

With time running out, Taiwanese lawmakers approved funds for buying U.S. weapons, fearing they could lose support if they didn’t act now. By Chris Buckley and Amy Chang Chien For months, Taiwanese ...