We could certainly have designed and launched a craft that would have a top relative velocity many times that of 70.2 km/s, if that had been a design consideration.

Since it wasn't, we're stuck with the slow pokes.

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If I set the budget, we'd have Ares and more. Unfortunately, I don't set the budget, and Ares is just too expensive and too far out for us to accomplish our goals within the budget we were given.

If we halt the ISS, all versions of Ares, and transport Orion and Altair aboard DIRECTv3's Jupiter family of Shuttle-Derived Launch Vehicles, we just might make it back to the Moon by 2020.