You understand that al qaeda is not full of peace-loving hippies that just want everyone to get along right? and that, at the ideological organizational level, they are not content with sitting back and allowing what they perceive to be evil to go unchallenged. It's not like they went from small town mountain thugs to world terrorists overnight. The leaders of that organization had, and have, the hatred and conviction in them to carry out the mass murder of people that they see as evil. Which is, realistically, anyone the western world, or anyone that reflects those ideas.
Read Zawahiri's book if you want to see just how far out there some of them are.