9/11 is absolutely fascinating to me, because it seems like it has left the entire world in a depression that exists into this very day. And i don't mean just, "oh its the 10th anniversary of 9/11 so sad" or even on the scale of 'horrifying tragedy that made people sad'. It seems to have had a profound and permanent effect on the mood of the entire world, i don't know if i'm mis-attributing this global bleakness and depression to the wrong thing but it seems like 2000-2001 was the turning point in the world's emotion.

TL;DR: is 9/11 why the present day is so depressing? Why? If not, why IS the present day so depressing? (for reference, present day = 2000 onwards.