Khleedril on Nostr: Firstly, it is very difficult and time-consuming to do that, secondly it is ...

Firstly, it is very difficult and time-consuming to do that, secondly it is destructive so you can't test actual chips in use, and thirdly it will only spark an arms race where the bad state actors learn from discoveries how better to hide their backdoors.

I suppose an approach may be to have ICs encased in clear plastic, and then they could be visually 'fingerprinted' against known-good implementations.