Both 9/11 and 7/7 had me worrying about my DBs. Younger for 9/11 (he was working at ORNL and used to be a frequent flier to the Pentagon)
And youngest used to travel round London with his job.
So both times as the news came in I felt a little queasy.
However here and now I surely can't have been the only one astounded - nay amazed - at the drone show. Mainly because I thought "well we no longer need artists impressions". Not only can you see where a building will go. You can see inside it if you want.