1) "Last fall, the latest war game was based on a Chinese biological-weapon attack that swept through US bases and warships in the Indo-Pacific region"

These are superfluous conditions (i.e. predicting bioweapons), and of course, and you're not going to hear about the 'real' results. And of course it ignores the after effects.

2) Defenders have considerable advantage in that situation, especially with a water gap. The 'amphibious assault' situation is severely hampered by the fact that even with air cover, all Chinese surface vessels are 'extremely vulnerable'.

Literally just a single, 2-man style team weapon system, if it could actually be deployed without sabotage, could make it nary impossible for such landings. I think it would be crazy for Taiwan not to have specialty capabilities against that kind of assault. Landing operations very dangerous for the landers.

3) Taiwan has 23M most of whom won't go down without a fight. It's incredibly difficult to occupy a place like that.

4) The 'angle' for China is likely political, and to land a vanguard of political operatives, saboteurs of all kinds, media controllers etc. and possibly to try a 'coup from within' as opposed to a frontal military confrontation.

5) Any direct military engagement would be met with pretty serious repercussions, for the first time maybe, from the West. It would be 'a big deal'.

If there were actually even a small US confrontation and say a couple of US frigates were sunk ... don't underestimate how Americans will rally under the wrath of that offence. 90% of the generally anti-war voices will quiet and look the other way while the 'other half' of the US releases the dragons in one way or another. If, as in the stated example there were 'Bioweapons' used against the US, then it would be WW3 level escalation and a nuclear standoff.

So again 'military confrontation' is a big deal, but 'military confrontation with Americans' is a much bigger deal they won't forget.

In either case, the tide of geopolitics will shift dramatically.

NPTO - the Asian equivalent of NATO would be formed instantly, with UK and EU as participating members.

TPP v2 - this would happen immediately and China would be de-facto ignored / out of the WTO.

There would be a China v. 'Almost Everyone Else' Cold War in which everyone would be forced to choose sides. In that scenario, there are actually very few places that would chose China, if forced. Aside from Russia, which would try to 'broker peace' (and of course Iran/N. Korea/Afghanistan/Syria) I think the only real holdouts would be in Africa, and they wouldn't be consequential. The Arab world would mostly go 'With the US/EU-led rest of the world' and so would South American for the most part.

6) We 'do business' with Taiwan in the hope that they can remain at least at their current levels of independence.

If China wants to take Taiwan and leverage the kind of spineless 'look the other way' artefact of our businesses and politicians they'll do it piece by piece, and/or make it look like a popular and legitimate 'coup' - and that Chinese forces are there 'only to ensure order and stability' and to 'protect democracy'. They need to give enough political cover to Nike, Pizza Hut and Apple to not pull out from China etc.. Kind of like Crimea, where we just 'forgot about it'.