I was at work, and stuff came over the radio saying that a plane had hit the world trade center. I remembered the story of a small single engine plane crashing into the Empire State building early in the morning, and figured that with all the airports in the area, t was probably just a tragic accident.
Went up into the office and started to watch it on TV with the boss, and boy oh boy did the shit hit the fan then. It was insane, and honestly, I hope never to watch anything like that ever again. Of course there's always that "one guy" that doesn't think it's a big deal and started getting shitty with me to get back to work, but of course that didn't happen.
Spent most of the rest of the day, and the next several months, glued to the news channel hoping and waiting for blood to be spilled. Say what you will about Bush, but he was the right president at the time for the job, and really handled things well, it's the monumental fuck ups later on that ruined him, but his 9/11 job was brilliant.