Watch 'Mars Industrialization Roadmap' by Casey Handmer. That is exactly what he...

radu_floricica · on Aug 3, 2021

The full conversation is a bit longer, and should veer into things like economic incentives: Mars will build nails pretty soon, electric screwdrivers a bit later, but microprocessors probably never, because it's many orders of magnitude cheaper to import them from earth, even if they have to sell electric screwdrivers in exchange.

There are quite a few steps to proper, long term self-sufficiency. You need the colonists to get there, to form a permanent settlement, to get to reasonable numbers, to make a place where people would want to raise families into, to get to a point where it has a balanced trade deficit and so on.

Everything up to here is mostly science fiction material, but if Musk lives long enough it might actually happen.

Now, from this point you need a nation-sized colony on Mars make a strategic decision to duplicate critical infrastructure on Mars just to be self-sufficient. This is the step that the OP with his panicked "must not put all eggs in the same basket let the rockets fly now" is not even aware it exists. As an order of magnitude is probably at least equal to everything up to then. Partly because it's objectively hard, and also because when you have a nation-sized bunch of people, you have to convince them to invest half their resources to build factories that will make microprocessors that by the time you finish will be more expensive than those imported from earth, and probably also obsolete. And you have to keep investing in such obsolete industries because a million people can't compete with 10 billion that don't have to manufacture their air. Multiply this for every domain where you need such critical high-tech industries, like medical.