|
Yes, materials will be important. We probably can't "do the same again", so much of the Industrial Revolution (from my reading at least) was started with the huge amounts of wood, then easily accessible coal, then "spending" coal to get access to deeper coal. If you started from scratch, there isn't really any easily accessible coal left. |
And consequently, those surviving and rebuilding are going to have the residue of a civilization that supported many more people to work with.
Cast iron might be relatively rare, but would it be relatively rare for 1/1000th as many of us?