A large part of the problem is centralization- if oil refineries or manufacturing hubs halfway across the world fail, we're suddenly out of supplies needed to f

A large part of the problem is centralization- if oil refineries or manufacturing hubs halfway across the world fail, we're suddenly out of supplies needed to function. The sort of collapse talked about here is scary precisely because it could happen everywhere at once. Likewise, because oil drilling depends on technology sourced from all over the world, you can't have a "local restart"- you'd have to reboot the entire planet all in one go. Historically, the "fall of Rome" wasn't as big a setback in human history as its made out to be- cultural progress shifted over to Persian countries, who kept on doing science and other nice stuff until Europe got itself back together. Meanwhile China ticked along unconcerned about the whole thing. It wouldn't work the same way in today's world, but that's a solvable problem. I've read about wood gas as a possible energy source for a non-global economy- non-ideal stuff in many respects, and requires the survival of a good amount of know-how, but providing a locally-sourced oil alternative in a pinch.