A few years ago a friend and fellow author Manu Saadia (author of Trekonomics: The Economics of Star Trek) posed a question to me about the viability of creating actual cities on other planets. It was, in his mind, one of the few things about Star Trek which seemed unrealistic, because of the fact that cities here on Earth thrive due to one important reason: imports/exports, i.e. resource exchange.

I’ll quote him below on his exact phrasing:

“[S]ettling a far away colony on Mars or a bunch of habitats in orbit is not a recipe for prosperity for these space-based outposts. Without fast and reliable means of exchange, I don’t see how these settlements could take full advantage of the network effects and of the endogenous dynamism of Earth’s great cities.”

He is correct in his assessment that, without the fast import and export of necessary resources, today’s cities simply wouldn’t survive. However, as I noted to him, I believe his strict reliance on economics, and much less so on technology, prevents him from understanding how interplanetary cities are still a viable prospect.

That is, he seems to completely ignore key technologies, such as 3D printing, which would directly address the current problem of importing and exporting resources from planet to planet. My own assessment was: