At least TSMC has finally agreed to build a cutting-edge 5nm fab in the US. And more recently this has been increased to 100k wafers per month, so the capacity is much larger than originally planned - TSMC has 120k wafer/month at their plant in Taiwan (Fab 18) so this will almost double the current capacity (although TSMC is building more capacity in Taiwan as well so this probably will work out closer to a 1/3 split of capacity once it's operational).
This has always been national-security leverage for Taiwan - if China ever attacked, Taiwan would make sure TSMC was destroyed and utterly cripple worldwide chipmaking. Like if you think the current shortages are bad imagine the only cutting-edge fab in the world disappearing overnight. That leverage only works if all of TSMC's facilities are in Taiwan so the idea that they would ever agree to build one anywhere else was absolutely unthinkable even a year ago.
The US must be playing some serious hardball given the shortages that have sprung up this year and it looks like they're getting results. First it was a little fab for national-security stuff and it's morphed into the US getting a gigafab.
On top of that Japan is getting a TSMC specialty fab - not power stuff, but it'll do CMOS sensors for cameras and automotive/embedded type stuff, and the EU is negotiating for a cutting-edge fab of their own. It's a huge sea change in the last year.
yeah it boggles my mind US spends Trillions on Military... yet large % of the chips powering every digital device we use (incl military) is made right next to China. Can you build a chip factory with a fraction of their budget... cmon
The US military actually goes out of its way to source domestic chips where at all possible. Currently this means a lot of Intel (or the older AMD/IBM chips made at GlobalFoundries I suppose), and there is a pretty significant amount of trailing-edge fab capacity in the US still, but you're right that it's not everything and there's some stuff they have to source from other countries.
That is actually the consensus reason (not sure it was ever stated outright) for the original plan for the 20k wf/m fab TSMC was building in Arizona (that has since been upgraded to 100k). Even if it wasn't necessarily a huge plant in terms of global supply, it gave the US defense/intelligence community a guaranteed supply of chips with domestic manufacturing and chain of custody.
It is nuts just how much of cutting-edge production is concentrated in the pacific rim region there, and the current shortages have really driven that point home even harder. Even leaving aside Chinese invasion of Taiwan, there could be a tsunami or some other natural disaster that takes out TSMC and that would just absolutely gut the worldwide economy. Imagine the current shortages where everything is still running at capacity, and then imagine that TSMC or some other major fab would go offline (Samsung getting hit in Korea, etc), be destroyed and take years to come back online - there are the same limitations as bringing new capacity online, you have to wait years to source new machines from ASML and so on.
It potentially could happen anytime. It could happen tomorrow. Just another big earthquake that sends a tsunami at just the wrong place and compounds all the current shortages even worse. Even apart from the national defense aspect, it is a dangerous concentration of irreplaceable supply chain elements and I think the US, EU, etc are really pushing to mitigate that danger a bit.
