"The agency is to begin launching a series of 12 robotic precursor missions to the moon in 2008. A new crew exploration vehicle will be built to carry astronauts back to the lunar surface between 2015 and 2020.

And during Bush's second term, analysts said NASA would have time to get the initiative off to a solid start by:

Launching an initial robotic mission to map the moon, measure the radiation environment and attempt to find stores of water ice at the lunar poles."
http://www.floridatoday.com/!NEWSROOM/spacestoryN1104PREZSPACEE.htm

As I said once before, Bush could be a great President. Three things that he is doing could bring this about. 1] War in Iraq 2] Fighting AIDs in Africa 3] Opening the space frontier.

I think the single most important thing that the govt can do to open the space frontier is determining whether and to what extent there is ice on the lunar poles. Of course, Smart-1 is already in route:
"ESA PR 56-2004. From 10 to 14 October the ion engine of ESA’s SMART-1 carried out a continuous thrust manoeuvre in a last major push that will get the spacecraft to the Moon capture point on 13 November."
http://www.esa.int/export/SPECIALS/SMART-1/SEMMRSZ990E_0.html

Now, I'm not sure how well Smart-1 will do as far as doing this and I'm not sure how well the next NASA robotic mission will do this. But I think it will help get us this point- it could simply function as to rule out the possiblity of minable lunar water deposits [if correct this is also very important to know]. But I think the "level" of detail needed is to be able to determine within a scale of a square km how much water is within the top 1 meter of regolith. [Probably the most important aspect of Smart-1 is the way in went to the Moon: ion propulsion and from the equator.]

Once we have a map of the lunar poles which can show the distribution of lunar down the scale of 1 sq kilometer [or better]. What will this map tell us?
Will it be a fairly uniform distribution, or will there be strong difference for one area to another. For instance over timescales of millions of years and over thousands of square kilometers, one will have a rain of impactors ranging from pebble size to size of city blocks. These larger impactor will affect water distribution at the 1 kilometer square scale.
If the total area of interest in a lunar pole is say a million sq kilometers and the timeframe is say 50 million years, how many impactor 30-60 meter range have impacted this area?