I just had a thought yesterday (or could it be the day before?) that America's obsession with emo music could be related to the rise of the Thief-in-Chief we know and love, Mr. President George Bush. A radical idea, but certainly if you begin to watch MTV and the dark imagery of videos by such bands as Hawthorne Heights and Panic! at the Disco (seeing that exclamation point, I wonder of they listened to Godspeed you! black emperor), you see the logic.
Although we try to cover it up, we are in economic and political hard times compared to the end of Clinton's era. I'll be honest and say that I can't remember Clinton as a president because I was only 10 years old when Bush stepped in office after the Supreme Court ruled such, but certainly, the rock music coming out of that time had a care-free, nothing-is-sacred, let's-be-immature-teenagers-and-strip-naked-for-laughs feel to it. Quite a foil to the serious nature of modern rock (i.e. this "emo" thing)
I'm certain some other person has came up with the same idea but can argue it more eloquently. Currently I'm running some google searches and am coming up with nothing.