There are only two human habitable destinations in the Solar System - the Moon, and Mars.
Besides basic scientific research and space tourism, what else are we supposed to do there?
We need to invest in space robots.
Planet Earth will eventually progress to Star Wars level space travel.
But, not for thousands of years.
It will NEVER be possible to approach the speed of light. NEVER.
See 53.
I agree about robots, but not about Mars and the Moon being habitable.
If humans cannot walk around without being sealed within a self-contained environment in a pressurized space suit, breathing the local atmosphere, in a temperature range that won’t kill them, then the place by definition is not habitable.
I believe venus could be made habitable much easier than mars.