The Pentagon wants to. They announced it July 7. The justification was security reasons. The building had already been attacked once, and it semed a bad idea to load up a known military target with children. (Remember that grief the US got from the press in the first Gulf War when the undergraound command center turned out to be loaded with civilians?)
The parents who work at the Pentagon see it differently, even those who don’t use the service. They were given 60 days notice that the service would be closed, without any alternative location opened. Basically, they were sent into the day care marketplace, in market where waiting lists to get in day care are way longer than 60 days. One argues that if there is real danger, the children should be moved out today.
This is a very good Washington Post story about it, but I think you have to register to read it. Here is a somewhat older Washington Times story.