Let's set aside the part that making a planet where we could live is hard. Just presume we did that, to start. Let's talk Logistics . Presume there are only 1 billion people left on Earth when we decide it's time to go. How do you get them there ? The gravity well holding us here (and holding the air down so we can breath it) is pretty darn strong. Today we're hoping to get cost-to-orbit down to around $100/kg. I wei…
We only have one Earth, and its the best home we could hope for. But we're crazy to keep all of our existential eggs in a single basket and hope it all works out.
> If we can make Mars habitable, we can make Earth habitable for far less cost.
That said, I absolutely love this sentence.
Although I would say, the technology we ultimately have to develop to survive on Mars or the moon will certainly help us keep Earth habitable.