The government isn't going to do it. That somebody, somewhere is us. And only us.
I'm 80 miles away. I'll do it.
Terrorism begets terrorism. That dark road must be avoided.
See you there!
Having said that:
#1) As an individual, never announce, publically or otherwise. Doing so will have already foiled any civil (or not so civil) attempt you may have been contemplating.
#2) Whatever is done needs to not play into the hands of the Islamic jihadists. This POS (that's Piece of Shi'it) needs to be barred from the site and completely humiliated in the process...not made a martyr of.
#3) New York City and its citizens there should rise as one to prevent this. They have until Monday. A wall of ten or fifty thousand people barring access is something in my mind that would accomplish number two above.