If the moon was such a critical military or commercial asset, operations would have already been setup there. The benefit has to outweigh the cost in any economic project and that is the basic reason why nothing has been setup there.
A missle program won't be installed up there. It costs $10,000 to send one pound of material into Earth's orbit and at least double that to get it to the moon. It wouldn't make any sense to install a missile program 250,000km from earth because you'd also have to invest in the fuel to propel the missiles all the way back. Military satellites are much more practical if anything like that were to happen, and there is a detection net setup in space to detect new and potentially volatile satellites.
There is no point in going to the moon just to be the one to claim it. Also, there is no justification to claim it. The moon is everyone's. It has been in our sky since the dawn of humanity. It's not an "asset". It's a celestial body.
By the time humanity is organized enough to even put a colony on it, we will probably have a lot of our social issues resolved on this planet, which means it would likely be a joint effort anyway. Space is a rough gig and we'd need as much help as possible. We should be dedicating those resources to research to terrestrial problems. We won't be able to make meaningful and major progress in space until we fix stuff down here.