Defense Historians Document 9/11 Pentagon Attack

In case you haven't seen this yet, Defense Department historians have just published a book on the 9/11 Pentagon attack
http://www.infozine.com/news/stories/op/storiesView/sid/24803/


I wonder if it answers three basic questions:
"How the hell did a bunch of amateurs fly a 757 hundreds of miles undetected and crash it into arguably the most heavily defended building in the world without even a single alarm going off to warn the occupants?" "Where's the 60 tons of 757 parts?" "Where's the video record of the impact, which was surely captured by several high-resolution Pentagon security cameras?"
I don't mean to be flippant about this. These basic questions have not been answered to my satisfaction.

Best regards, Alan