Comment by gadders
I think it cares about Taiwan as a democratic country but I think the chip fabs are becoming a geo-political factor as much as oil fields or other resources.
i.e. we don't want [Russia/China/Whoever] to invade Country X as Country X is an ally and a democracy, but as Country X has [Oil fields/Chip Fab/Lithium Mine] we REALLY don't want them to invade.
The difference between an oil field and a chip fab is that the equipment is more easily destroyed in a chip fab, vs a hole for an oil well. Not to mention that expertise in human capital required for chip fab is way higher than that of an oil field.
Even a successful invasion of taiwan guarantees either the people important to the fab will leave, and the equipment evacuated, or destroyed if unable to evacuate.