I think our technology is primitive at a level that we can't comprehend. Like an ant that has wandered into a steel mill. We see things, but can't possibly understand them. In fact, what we see is in the past. The further away it is, the more distant a time it is. Even your own vision is not suited for space observation.

Humans are creatures of mind, body and spirit. Neglect even one of them and you suffer. We will require food, water, heat, cooling, oxygen, light and other creature comforts required to maintain. Obtaining them, lugging them about the cosmos, storing them and preserving them. Quite a tall task.

One day, locomotion about the solar system might be a thing. It will be nowhere near like we imagine it though. I suspect it will be practically instantaneous travel similar to what we think of a wormhole. There is no possible other way to do it with a finite lifespan and mortality. Speed kills. Gravity kills. Toxic gas kills. Radiation kills. Cold kills. Dust kills. Any major problem with the ship kills. Any major problem with you kills. Anything we just didn't think of will probably kill too. What if lunar screw worms awaken only once every 500 years, and we just don't know about them yet. What if they like to molest their dinner before eating it?

We get no plan B. We should focus our efforts in the here and now. Failure to do so is extinction.