Comment Re:We need a national science and engineering agen (Score 1) 308
Given that, in your words, we have a readily available means to keep our species alive for the medium to long term, the focus should be on making Earth more hospitable for us, not on space exploration. Focusing on making space hospitable is akin to trying to develop an iPod before the record player. Certainly there's some benefit to be had, but if the long-term survival of the species is truly important than the order of operations is important, and wasting resources now on making space hospitable is just that: wasteful.
I think you may agree with me on principle with this: you said the only way to ensure our survival is to be sure a world catastrophe doesn't kill all humans. Given the size and resiliency of Earth, the access to materials, and the known working environment, making a sustainable and hospitable environment here that would withstand catastrophe is a far easier plan than making one that would survive catastrophe outside Earth.
This is true even with your asteroid example. Like I said in my first post, Earth's worst day in the last billion years was a picnic compared to Mars' best day. People consistently underestimate Earth as a hospitable place, and underestimate space as a hostile place.
The absolutely best path is to make sure we can survive on Earth before we try to survive out there.