TSMC is a part of it, but the whole invasion plan is mostly out of shame. China wants to reclaim what they believe rightfully belongs to them.

The TSMC was created as a country’s defense strategy, it’s commonly referred to as “silicon shield”, but Taiwan’s over reliance on it and lack of military investment of their own prompted US to reduce the reliance of TSMC so that they would have a choice if they want to defend them or not.

And invasion is risky for China too, even without US intervention. China is being supplied millions upon millions of chips by TSMC as of today (low to mid-end) and if they invade and TSMC fabs gets damaged or sabotaged they lose all that supply.