Especially now that Taiwan has removed restrictions on producing TSMC's most advanced nodes on foreign soil.

https://www.techpowerup.com/331104/tsmc-granted-government-p...

I wouldn't count on that. It's going to be some time before the Arizona plant is fully operational, and it's not a substitute for the production capacity in Taiwan. It's also very possible that TSMC will pause or halt production in the US if they're targeted by trade sanctions.

The TSMC Arizona plant is already operational they started production of TSMC 4nm process node this month, and will be ramping up volume over the next few months.

https://www.reuters.com/technology/tsmc-begins-producing-4-n...

TSMC is also looking to add a chip packaging plant in Arizona.

https://pr.tsmc.com/english/news/3174

Amkor will also be near

Even so, the ramp-up to full capacity is going to take a while - and even at full capacity it's not going to be a replacement for the facilities in Taiwan.

They don't have to replace all of the Taiwanese manufacturing, just the chips that are US bound. There are plenty of customers in other countries that need TSMC chips.

Besides the fact that the AZ plant does not produce TSMC's bleeding edge process (3nm) but the older 4nm, the product from that fab can't be delivered directly to a customer. Every wafer at that plant has to be shipped back to Taiwan for packaging and can only then be delivered to a customer.

So a blanket tariff would definitely apply even to the production of that plant. Which is why lots of CEO's (including Tim Cook) are trying to suck-up to Trump right now, to get an exception made for their imports.

TSMC can work with partners for packaging (TI and IBM come to mind)

Packaging is not trivial. I don't think either of those companies has been near the frontier for packaging in ... more than a decade? Two decades? This would be something where it would take a lot of time and throwing away badly packaged wafers to create the experience necessary. TSMC is probably better off doing it themselves in a new build versus working with partners who are so far from their level.

That is in an international economic zone and would be subject to tariffs as well as for supplies.

The point of the foreign trade zone is no tariffs, avoid customs. And the point of the tariff is to get plants built in the US, so tariffing them would make no sense.

And yet!

The plant in Arizona is deliberately not equipped to produce current-gen chips.

Did you forget the sarcasm flag?