I've never been good at anniversaries...
I don't much go in for jingoistic up-team patriotism and its attendant bullshit.
My opinions about the event of September 11th, 2001 anf my government's responses to it, which continue to affect large swathes of the world are...complicated.
That said, this is a beautiful thing, and should be shared widely.
http://nielsenhayden.com/110.html
https://youtu.be/UrMo3TaI8mo
Read the first before watching the second, if you aren't already familiar with it.