Europeans didn't go to the Americas just for their crowns. Why don't we think in space travel in more economic terms? Image from Anthonares.
Of course, people do things for reasons besides creating material wealth - we do things to create happiness, and wealth is just one (major) route thereto. Net-consumers of wealth (like entertainment) are okay when it's merely entertainment that feeds happiness without doing TOO much damage to the material bottom line - but when we're eating up many billions of dollars in some pursuit, the question of return on investment becomes much more important. Even the comparatively cheaper (in terms of national investment) European adventures across the Atlantic centuries ago were at least partly business ventures. If we want to see space exploration continue, it must become a profit-making enterprise.
Gravity wells are expensive. Enterprising aliens may warn us that the really scary thing about black holes is that they're terrible for profits.
As our economy now operates, the obvious revenue source from operations in space would be metals. The main expenses are getting out of gravity wells, and keeping humans alive. A path forward would then be:
- Improve automation (as is happening independently) and machines' ability to operate in vacuum and zero gravity
- Focus on obtaining commodities from small asteroids (this article breathlessly mentions "trillions" but fails to appreciate the impact on a commodity price when a whole planetoid of it is dumped on the surface.) Anthonares has a good quantitative exploration of the concrete economics of commodities and space-mining.
- Focus on a way to get the ore down from orbit (we don't need a space elevator. When you're dropping something, simpler technology works; you just need clear ground underneath it. Antarctica?)
- An application for self-reproducing automata - if the next-generation automation could make more of themselves out of nickel-iron-iridium, and obtain fuel from the carbon compounds in chondrites, you've just solved the expensive gravity-well problem.
A RepRap device, which is a 3D printer that can print large portions of itself. If it could make itself out of iridium and/or nickel and/or iron, we're halfway to von Neumann probes. Aliens are more likely to meet RepRap's descendants than to meet us.
Note that a single expedition could pay for itself in commodities, but there's a considerable funding hump to get over. (If you think the development time for pharmaceuticals is hard, you haven't seen anything yet.) So there is still a role for those deepest-pocketed, longest-term-thinking of institutions, governments. Depending on your political tastes, this could be anything from tax incentives for private industries, to dedicated government research labs.
As an aside, I've argued before that we're most likely to recognize other intelligences by the self-reproducing tools that are spreading out from their point of origin (their von Neumann probes) rather than their signals, which may be in a medium that we don't know about and in a pattern that we cannot recognize. (Apparently the as-yet-uncontacted hunter-gatherers in the Amazon have somehow missed all our radio broadcasts. I bet they think they would know about all their neighbors.) It's intriguing to think that the first replicators we encounter may therefore be alien mining equipment.