Thanks very much for the Reply/insights.
I could be wrong but at least intuitively speaking I think it would be far less possibility of a cost overrun or excessive cost expenditures (given already a 20 trillion $ US Federal deficit) if the ISS was "retrofitted" so it could detect NEOs coming...
The B612 Foundation,
http://en.wikipedia.org/wiki/B612_Foundation
http://b612foundation.org/
is a nonprofit composed of astronauts, scientists and engineers dedicated to the cause of developing a technological early warning system to detect distant asteroids that might be future dangerous...