If you weren't there (which I wasn't) it's really hard to imagine the power of the collapse of the world trade centers.  This image was taken a short while after 911 very near ground zero.  What you're looking at are Venetian blinds that were blown all the way from the trade center and ended up being mangled in the branches of the tree.  Can you imagine the horror felt by those that were there?  I hope we never forget.