I remember that episode ! That part always scared me , in a useful way though . I always look out for large flammable piles now . <| sep |> I ' m still waiting for the source images , thanks in advance <| sep |> They were being warned by our own Intelligence Agencies , and foreign intelligence agencies that a Terrorist attack was about to happen . I believe it was like 2 weeks or a month prior they knew that planes would be used to do the attack and that it would be very soon . However , what are they to do ? Shut down every airport ? Put armed guards everywhere ? How many reports like these were they getting every year ? I don ' t know the answers to these questions , but they were absolutely warned by basically the entire world including Russia that it was going to happen .