The US and Taiwan don't have military alliance. The Taiwan Relations Act is carefully worded to avoid any commitment and maintain strategic ambiguity and keep both sides in check. The strategic interest of the US is limited in terms of the cost of defending Taiwan.
The article and many articles like it fail to explain the big picture. The US has indirect way to counter Chinese aggression. Sea blockade from distance where the US has military advantage would cut almost all sea traffic to China and isolate it from the world economy. Chinese are well aware of their position as a logistic cul-de-sac. The Belt and Road Initiative can be seen as long term strategic plan to go around this problem. It loses money but Chinese need it to work so they do it anyway.