Ask HN: How do you propose to rebuild industry in a post-apocalypse world?

Context: https://en.wikipedia.org/wiki/Solarpunk https://news.ycombinator.com/item?id=43236520 I love the concept of Solarpunk or anything similar. However, I fail to understand how to reboot modern industry in a post-apocalypse world. Scenario: I think a deadly virus outbreak is far more likely and devastating than a thermal nuclear war. Let's assume that such an outbreak took out most of the governments and the population, and only local communities start to show up afterwards. How do you reboot modern industry? I'm sure we can scavenge stores and storehouses for a while, but eventually we need to rebuild a very large portion of modern technologies, if not all of them. For a start, how do we produce steel, aluminum and other common metal from raw materials? How do we actually mine them? How do we product antibiotics, needles and everything we need in a hospital? How do we build roads (I think this is actually not too hard)? How do we build transportation tools -- for sure we do ... Read full article.