4/5nm are still marketable nodes, but they're getting fairly long in the tooth. Intel's foundry which has been getting a lot of negative press is more advanced than the TSMC AZ tech.

Then, there's the other issue that the wafer production is step 1 of a microelectronics supply chain. It does little good to build a wafer in the US that has to be then shipped to Asia for it to be made into something manufacturing in the US can use. There have been a couple recent announcements about wafer test and packaging facilities coming from Asia to USA, but those announcements are early and will take 2 or three more years to come online. Amkor got CHIPS act money to do this and so we'll see how it comes along.

The CHIPS act opened the door to a world where the US isn't left completely empty handed in the event SE Asia destabilizes. But it's a drop in the bucket by comparison with the rest of the microelectronics market.

I would draw an analogy to the strategic petroleum reserves in Louisiana. They're not meant to actually impact the global petroleum markets. It's just in case...