Osama for years has been saying Roman and the Vatican is the capital of the enemy and is a major target.
December 2002, three months before the US invasion of Iraq, al Qaeda began issuing a stream of fatwas designating its main operating theatres in Europe. Spain was on the list, but not the first.
1. Turkey was first. Islamic fundamentalists were constrained to recover the honor and glory of the Ottoman caliphates which were trampled by Christian forces in 1917 in the last days of World War I.
2. Spain followed. There, al Qaeda set Muslims the goal of recovering their lost kingdom in Andalusia.
3. Italy and its capital were third. Muslim fundamentalists view Rome as a world center of heresy because of the Vatican and the Pope.
4. Vienna came next because the advancing Muslim armies were defeated there in 1683 before they could engulf the heart of Europe.
Here's a historical date, c/o Hilaire Belloc, The Great Heresies: "Vienna, as we saw, was almost taken (by the Mohammedan army) and only saved by the Christian army under the command of the King of Poland on a date that ought to be among the most famous in history -- SEPTEMBER 11, 1683."