There hasn't been a major terrorist attack in the US since 9/11. Remember when people seemed certain that another attack was going to happen? Some people acted like they knew more about bin Ladin's inner circle than they knew about what their own kids were doing after school.
Let's face it. Terrorism is so much more fun to talk about than the economy. Timothy Noah has an 8 part piece detailing various theories on why we haven't been hit since.