How would that work? They can't take the fabs (single door opened and dust makes it all useless) and even if they could they can't run ASML machines with their support. So... labor camp fabs on unmaintained STOA hardware from a single company everybody relies on? I can't imagine that scenario. Either they manage to redeploy the whole value chain (not saying it's impossible but doesn't seem to be the case at scale for now) or taking Taiwan by force is mostly a political show, not a technological one.
China is working hard on getting their own fabs. Then the have no need to keep TSMC operational.
Simple, they invade and TSMC blows up their factories. Or, the invasion is successful and they control the factories.
I didn't say it was likely, but one of these two outcomes is possible.
They need regular chemical deliveries from japan as well.
If TSMC were to simply disappear, it would be a great day for Samsung/Intel but a godawful catastrophe for most HPC applications and consumer hardware. People aren't afraid of a fab takeover, they're afraid of TSMC disappearing altogether.
Wouldn't the rest of the world encourage ASML to keep supporting the fab because they want the chips to keep coming?