There are two paths to making this work. One is domestic production, which as you say might work for the United States, but the other is supply diversity. If you don't have a local industry but there is one in Canada, Germany and South Korea, and those countries are your allies, you're probably fine. The issue comes when you're entirely reliant on a single country (e.g. China), especially when that country is undemocratic/authoritarian. Because that makes it too easy for them to betray you without you being able to do anything about it, significantly increasing the probability that they actually do it.

I would think countries would take a cost and risk-based approach. Countries that have the means, and who face major risks from a compromised supply chain compared to other standing risks, might want to think about moving things in-house.

Honduras and Nigeria might have other, more pressing concerns. Liechtenstein in particular is a financial center with an extensive manufacturing base and attendant expertise, so it might be worth considering for them.

wrt computers, why not if they're capable and willing? it has increasingly obvious and critical security considerations. russia already has a fledgling domestic processor industry for these reasons:

https://thenextweb.com/insider/2017/05/25/russia-showcases-f...

It seems like the main fabricators based in Russia are still working on getting below 90nm.

Poisoning a population or depriving them of power is a great way to start a war. Peeking at their computers is merely espionage. So yes, food and power might be more important, but there exists sufficient political deterrent already.

It's not even terribly hard. AFAIK you can buy all the tooling quite easily, and it's a well understood problem.