[spodek]

To propose we go to Mars to protect the species is backward. People with the means want to go to Mars to show off or other personal reasons. Then they drum up some humanitarian-sounding reason for government and popular support.

If we could prove beyond shadow of a doubt that no dangerous asteroids would hit Earth for a million years and that pursuing Mars accelerated our environmental problems here, I don't doubt that the same people would come up with new justifications and keep going, even if counterproductive.