Re: economy's role in long wars
For the US, the question is will China trade all of China for LA or Taiwan. The US must also come to the conclusion that China won't, so the US can rightly ignore Chinese threat over LA and push the Chinese back from Taiwan.
See where this gets you?
The question is not whether China will risk nuclear war over Taiwan. The problem is the current US plan envisions massive strikes against Chinese mainland as part of any conflict with China. Chinese defensive systems have advanced to the point that US forces can't just standoff and prevent a Chinese landing or blockade without first strike mainland targets such as, command and control, short and medium range ballistic missiles, antiship ballistic and cruise missile, OTH radar sites, long range AD missile and radar sites, as well as airfield and naval facilities.
Unlike back in Korean War days or even in 1996, US can't afford to give Chinese mainland sanctuary status anymore without taking disproportionate casualty or even lose.
If Taiwan declares formal independence (unlikely), China will go to war (by law as well as overwhelming public sentiment), US will attack Chinese mainland. The fight will not be over Taiwan at that point, it would be a fight for China. Now if Chinese leaders see B-2s approaching China, how do they if they are attacking DF-21s or DF-31s?