[youtube=560,345]FaidaE1ZxrI[/youtube]
For me, it was probably a couple days, but as others have noted it was done in a manner to cope with the attacks. On the purely intellectual level, I had known for years that it was just a matter of time before something like this happened as a result of our meddlesome foreign policy, but I had always expected it to be a bomb in a subway or something like that. Flying planes into buildings was pretty shocking, which is why I'm sure they did that as opposed to strapping bombs to themselves and then going to a mall or something.
It was probably a couple of years before I started making fun of people who were obviously using 9/11 to achieve some end, whether monetary or political. These days "remember 9/11!" is kind of a punch line that me and a couple friends say to each other whenever someone says something stupid and hides behind patriotism to do it.