It's the tallest building in Italy, so it sure would get the attention of Italy. (Why Italy? That's the part I don't understand.)
The Vatican is not a tall, easily-hit item. May also be hard to see from a distance. Consider that the DC 9/11 plane flew right over the White House - a likely and distinctive target, yet hard to see from the air. Instead, they went for the Pentagon: a huge unmistakable building with wide open spaces around it. The Vatican is likely not quite so large, distinctive, visible, or surrounded by low open spaces.
Also - so far - Bin Laden & Co.'s rhetoric has said nothing about religious differences, i.e.: Islam vs. Catholicism. They're not after devout Christians, they're after agnostic/athiestic capitalists - hence the focus on places of business and politics.
I have a hard time accepting this, according to many at FR, Islamics are out to wipe out Christians and Jews.
Being a capitalist doesn't make you an atheist or agnostic btw.
Two possibilities : 1. Italy is seen as a fairly conservative EU country, which has been more supportive of GWB than most EU members.
2. Italy has the EU's highest proportion of Muslims at 13% of the population (it and Spain are the highest ; the rest of the EU ranges from 5-8%. This is in contrast to the US, where no more than 2% is Muslim, and even that's been said to be an overestimate.)The high number of Muslims would make it difficult for the Italian government if that 13% , or a fairly large percentage thereof, were to run amuck in response to anything their "muslim brothers" were to do. IOW, they can celebrate in the streets with impunity, same as if they were in Egypt or Iraq.
I take it you've never been to Rome.
Just a few days ago a vote was held in the U.N. supporting the Palestinians and condemning Israel. Only 5 countries voted in support of Israel, and I believe that Italy either voted on the side of Israel or abstained from the voting (someone please correct me if I am wrong).