If intelligence is a topic which is of interest to you, go read this article. It starts by noting a document about Iraq and Jihad, read by a Norweigen defense researcher in December of 2003. The document outlined a strategy to dissolve the coalition by striking at America's allies, particularly Spain. It was read and then forgotten by Brynjar Lia until the March bombings in Madrid.

This article does a great job pointing out exactly how difficult the intelligence business is:

But why didn't Lia grasp the document's apparent importance immediately? His initial hesitation underscores the difficulties intelligence analysts face in monitoring a foe whose tactics constantly evolve within an ideological framework that is itself strategically flexible. Those problems are compounded by the chaotic nature of the Internet, which has become one of the jihadists' preferred means of communication. "There are literally hundreds of Islamist Web sites and, at times, up to 50 different addresses related to al Qaeda alone," says Gabriel Weimann, a fellow at the United States Institute of Peace who has been tracking Internet sites for seven years in his work on terrorism and the mass media. "The great challenge is telling who is authentic and who should be analyzed."

Difficult business indeed.