No, YMTC's supply chain audit was to find the dependencies in the first place, not because it was dependent. The supply chain goes deep and dependencies come up in unexpected places.
The point is that in the semiconductor industry, the machines are generally made entirely in the West.
Yes, the US would find some unexpected dependencies, but the nature of this technology means there are comparatively few to deal with.
In terms of lithography, how many Chinese sourced components do Nikon or ASML actually use? The machines were mostly designed years ago, so my guess is barely any.
And my guess that the YMTC still has a lot of machinery suppliers who obtain components from overseas. That will change in time, but I don't think it's the situation now.
It seems that you are convinced that just in time supply chains are highly resilient, black box subassemblies are easy to find full replacements for and it's super easy to reverse engineer and produce complex custom mechanical parts that have neither vendor documentation nor anything beyond a serial number. I've never seen that to be the case, historical precedent including the Saturn 5 rocket hasn't shown that to be the case, but maybe you know a case.
Just in time supply chains are not resilient. And if you think about it, most components in products are not black box subassemblies.
Most products are actually fairly simple, with the most complex parts being the electronics.
Cars are probably the most complex mass-market product in the world, yet supply chain audits happen fairly easily.
And we've seen many of the supply chain vulnerabilities in world already appear over the past 2 years with all the COVID disruptions.
I don't know where you get this confidence from. So has anything like this ever happened historically? Please, enlighten us on that.
It goes back to how long it takes to reconfigure or produce an entirely new industrial supply chain. The best analogues are what happened during WW2 when trade links were severed and the various countries had no choice but to build alternatives.