[RightWhale]

there could be thousands of old mining traces in our own Belt

Seeing as how we don't have much info on what happened right here on earth even 10,000 years ago, and we have just begun to look around the other planets and asteroids in the solar system, the possibility that others have come and gone many times cannot be denied. Just because we don't see them now doesn't mean they never passed through gobbling up this and that on the way.

[Senator Pardek]

As you know, it's theorized that those beings on any given planet who are the most intelligent sprung forth from predators.

In 100 years, every nation on this planet will have the ability to destroy all of humanity with ease. There will still be Osama Bin Ladens - I truly doubt that man will ever reach the stars because of these facts.

I believe Sagan was right when he posited that "advanced" civilizations, by definition, will wipe themselves out (long before interstellar travel is achieved).