Can you explain why we haven't been back to the moon?

If you know me, you know this is a rhetorical question. I personally believe it’s far more likely that we already have some kind of secret space program and/or base on the moon, but I’d like to hear a reasonable argument for why we haven’t returned.

Is there any other scientific endeavor or application of technology that has regressed as completely as travel to the moon?

http://www.telegraph.co.uk/scienceandtechnology/science/space/5760285/Nasa-experts-scale-back-moon-and-Mars-plans-in-face-of-Obama-funding-cut-fears.html