Dubya is desperate. Now that his personal war on daddy's enemies is effectively over, Dubya need a new catch to draw in money. The fact that he chose the space program is probably the one smart thing he's ever done, though.
The Ion engine is far from being able to propel men to Mars. The engine works far too slowly for such a short distance when you can only accelerate half the way there. Now, if we were going to Titan, Ion drives would be perfect.
The space elevator idea, while a fun thought, is totally infeseable. Along with the massive size of the base cables, you'd also have to wait a week or so to get to the top without rocket engines installed on the bottom. Why not just use shuttles? You'd spend the same money on fuel, supplies, and 'Oh S**T!' provisions without the massive cost of building this thing and developing a metal that can withstand the punishment.
The moonbase idea is just like the space elevator idea. A fun thought, but not possible at this time. Sure, scientists say that there is water under the surface of Luna and Silica, Titanium, Oxygen, and other elements in the dusty soil. But the cost of building such a structure along with the cost of supplying it until it got on its feet would be much too high for it to be accepted as an international project. And what if the scientists are wrong? What if there is no water?
Just my $.02...