reply to post by mars1
It's not like we don't do it to the Earth thousands of times a day!
What's the problem?
Sept. 11, 2009: NASA's Lunar Crater Observation and Sensing Satellite (LCROSS) is racing toward a double-impact on the moon at 7:30 am EDT on Oct. 9th. Today NASA announced exactly where the crash will take place.
The target crater is Cabeus A. It was selected after an extensive review of the best places to excavate frozen water at the lunar south pole.
Possibly the strongest evidence for it to be a 'hollow ob-ject' comes from the fact that when meteors strike the Moon, the latter rings like a bell. More specifically when the Apollo crew in November 20, 1969 released the lunar module, after returning to the orbiter, the module impact with the Moon caused their seismic equipment to register a continuous reverberation like a bell for more than an hour. The same effect occurred with Apollo 13's third stage which caused the Moon to ring for over three hours. So what's going on with the Moon?
LCROSS will create a 6-foot-deep crater inside another crater on the south pole. The moon has suffered much worse from the cosmos, and this latest gouge pales in comparison. Note that there are no explosives on board—the mass of the impact alone is enough to create a plume. Also, the craft will be empty of all fuel before impact, to keep results uncluttered.
NASA's plans to send a man to the moon and beyond have been derailed by a lack of funds and the US human space program "appears to be on an unsustainable trajectory", a presidential panel said.
Hi-res pic from hubble where exactly can we see any pic's of the moon from hubble

But it is quite a disgrace to do this, I am sure there are other methods of learning about the moon
...and as you say, it's the world's and mankind's moon (unless someone else we don't know of lays claim to it from elsewhere)...
...and there's no good reason for this except to flex muscles and show the world that if you can bomb the moon, you can bomb anywhere on Earth too.