Doesn't the government already make use of IBM's manufacturing capabilities for Top Secret+ chips to try and mitigate the risk of this scenario?
My understanding is that the main concern here are chips in COTS equipment bought from countries that are considered by some to be untrustworthy.
Allegedly the government requiring a domestic fab for some chips is one of the biggest reasons IBM's fab remains funded.
All hearsay though.
Lots of secure labs run on the same Dells and HPs that everyone buys