You should run a comparison. If you could wave a magic wand and erase the startup costs with mining space resources to produce our heavy industry, would the operational costs (transport costs/etc) be less than they are right now? I think it would be, it's just the startup costs are ridiculously high. So it's likely to be the case that you never make back the initial investment. However if someone's driven and has the capital, they could get that set up and then beat out the rest of the industry.
Now I'm not saying it's a foregone conclusion that it'd be cheaper, but just that it maybe can be.
Now I'm not saying it's a foregone conclusion that it'd be cheaper, but just that it maybe can be.