1. To recapitulate Al Q'aeda's success in pushing Spain out of the Coalition, and out of Iraq.
2. To do it while the G-8 is meeting in Scotland, forcing Blair to break up the conference -- it's a message to the G-8, something along the lines of, "we are the powerful ones -- you must appease us!" Straight out of the Sect of the Assassins.
3. It may not be over yet. They may yet make a play for a major political figure -- Blair, Bush, the Queen, maybe Putin.
Prayers for London, our leaders, and all of us.