[author]

I agree with you that this is silly, and don't recommend it. It looks to me like even in an EMP situation, you don't need a Faraday cage, you just need your equipment to be unplugged: "Overall, I think it's pretty likely that for EMP resistance it's enough to leave your equipment off and unplugged. Unless you're excited about testing Faraday cages, make sure your stuff stays unplugged and you can stop reading now."

On the other hand, I don't think we can rule out a lot of situations in which an EMP might be used, even if none of them involve an AI directly trying to kill people. For example, other countries could conclude that risking nuclear war is a better bet than allowing the US to build superintelligent AI.