Nobody else than Paul Wolfowitz said the following remembering 911:
Wolfowitz: We were having a meeting in my office. Someone said a plane had hit the World Trade Center. Then we turned on the television and we started seeing the shots of the second plane hitting, and this is the way I remember it. It's a little fuzzy.
Q: Right.
Wolfowitz: There didn't seem to be much to do about it immediately and we went on with whatever the meeting was. Then the whole building shook. I have to confess my first reaction was an earthquake. I didn't put the two things together in my mind. Rumsfeld did instantly.
Q: Did he really?
Wolfowitz: Yeah. He went charging out and down to the site where the plane had hit, which is what I would have done if I'd had my wits about me, which may or may not have been a smart thing to do. But it was, instead the next thing we heard was that there'd been a bomb and the building had to be evacuated. Everyone started streaming out of the building in a quite orderly way. Congregated on the parade ground basically right in front of the Pentagon which would have been about the worst place to have a crowd of a couple of thousand people in that moment if we'd again had our wits about us. But we were out of the building anyway. http://www.defenselink.mil/transcripts/2003/tr20030509-depsecdef0223.htmlAs far as I can see this is new and certainly deserves an explanation. It is unlikely that Wolfowitz needed still in 2003 an explanation why he sat on his hands on 911. Apparently he didn't go into the NMCC in time neither.
I'd like to point out as well the well-known supra-natural powers of Rummy. He's at the other end of the building and knows immediately that a plane hit it. Remember you couldn't be further away from the crash site than him. Moreover the first thought most people in the Pentagon had was that it was a bomb.