Another thing that occurred to me was that an AQ document discovered about a year ago announced that they planned to attack the weakest (politically weakest) members first, hoping for a domino effect of fear. They regarded Spain as weak because the media and left was so opposed to Spain's support for the US, and Aznar was basically going it alone because he thought it was the right thing to do.
I think that Italy would also be weak, in terms of security and in terms of popular willingness to stand up to an attack. As for Britain, I don't know - the Brits (particularly their treacherous leadership and media) were very opposed to Blair's support for us, but I think they might actually come to their senses if they were attacked. So my money is not on an attack on Britain - yet.
"I think that Italy would also be weak, in terms of security and in terms of popular willingness to stand up to an attack."
I agree in terms of security, but not of willingness of the people. Their weakest point in terms of security lies in their geography - too much coastline and two major islands to protect..