Because of the freedoms and religious differences in Spain. You know, the same reasons as 9-11. It has nothing to do with the previous 50 years of foreign policy intervention in the region, massive taxpayer subsidies to Israel, American troops stationed in Saudi Arabia going down the roads in convoys everyday, giving Saddam weapons of mass destruction to fight Iran, or funding Osama bin Laden against the Russians and then cutting him off. Nope, Spain isn't a pure Islamic government and they have too many freedoms. You know, the same reason they attacked us. Why did the American government support these same terrorists that are attacking everybody right now is the better question.

The above paragraph is such a condensed pile of BS it must surely bend light.

Maybe this wasn't about Iraq. Maybe it was about Ferdinand and Isabella kicking out the Moors in 1492. Or maybe it was just a target of opportunity - AQ has the money to buy bombs, ETA has the people to plant them... It made such a good opportunity they broke their 2-1/2 year pattern of targeting Muslim countries, the French, and other appeasers. But they're still not up to attacking in the USA. It's better to be their enemy than their "friend."