Monday's CCNet has article discussing NEOs. I thought this was interesting bit by Benny Peiser ... "We should bear in mind that 99.9% of all species
that ever dwelled on Earth were wiped out, most likely, as a result of large
impacts.

As long as we remain incompetent to take full control over these destructive forces, any over-optimistic undertone regarding asteroids and comets seems untimely to me. We need to get our priorities right first. The anticipated opportunities for science to take advantage of and exploit NEOs for space exploration remains an ambition for the distant future. In order to bring this long-term goal to fruition, we need to learn how to reshuffle the cosmic game of dice to our advantage."

Even though I think NEOs could serve us well in developing space; I believe Peiser is placing the correct emphasis/priority. The idea that rocks impacting Earth at high velocity have been a "good thing" story is somewhat disturbing to me. Space rocks over the long term are a serious threat to anything living on this planet. That humans are mostly ignoring this threat is probably due being distracted by too many other issues which may be insignificant in comparison.