I have always had my theory on the attack and just how much the government and airlines knew. The airlines were aware of something back then... I was flying back from a family wedding and on 9/9 (maybe 9/8) was stopped at the airport for my pocket knife in my carry on bag. The nice security agent (a sweet little old black lady) said "it is something new we have to start looking for." . Those words will forever be burned into my memory.
Also, that airport had a TON of plain clothes military types there that day, which this was a small airport I was flying out of back to Boston.