Colonize Mars?

Mars was once geologically active (if not presently) and has traces or hints of once-flowing liquid in its surface. Scientists speculate that underneath Mars' surface, there could be life-supporting substance which may be tapped to transform Mars into a living environment.

Manned mission to Mars before 2020? Well, the cost of Iraq war was just about the same cost as this space mission, so why not. Transform Mars environment, the size of 1/3 of Earth? Maybe not in the next 500yrs? or a thousand, if that's even possible...