Al Qaeda's smartest move...

... is relatively easy: Kill John Kerry and John Edwards. It wouldnt' take many people, and wouldn't require the level of planning and resources of 9/11. And the effect would be just as great, if not greater. Think of it. Who will be blamed for this? Bush. Forget even if they take the guy/guys alive somehow, there will be a part of the Left which will blame Bush no matter what. The attack will be seen as the first step toward a dictatorship, and will likely lead to riots. Al Qaeda wouldn't have to do the damage themselves, American leftists would do it for them. I can think of few other things that would lead to as much havoc. Hopefully, AQ hasn't realized this yet. At least the Secret Service knows their stuff...

UPDATE:

I suppose I should also mention my surprise that Al Qaeda hasn't tried to assassinate Bush yet. I mean, not attempts, no nothing. At least, nothing that made the news. I would think that they would have been able to get at least 1 person close enough with a gun. Perhaps they just don't think it would be worth it. Or maybe we have been lucky thus far. Or perhaps they are intending a very sophisticated attack with much better chances of success.