I have no doubt George W. is going to give serious payback- here's my prediction:

The US finds somebody or some group responsible. This person/group will be holed up in Afganistan or Iraq or some such place. US demands deportation of these felons- the government of Afganistan or wherever says No Way- gets other like-minded (muslim?) countries to back them up.

And all the ingredients for HUGE incident (i.e. Gulf War ass-kicking time 10) are mixed together.

I'm just curious if the the US gov. would actually break out the nukes. They brought Japan around pretty quick last time.