Bush hopes that voters have national security on their mind as they pull levers or touch screens or puncture chads. But since there isn’t a lot of objective data to go by (have we killed more terrorists than we’ve created?), it seems like the one big truth that we know for sure should loom even larger. [The Bin Laden video] was quickly dubbed the “October Surprise,” but the real surprise is something different: It is that, despite warnings by U.S. intelligence that al Qaeda was planning a pre-election attack, it hasn’t happened. Indeed, there hasn’t been a terrorist attack on U.S. soil since Sept. 11, 2001, and the intriguing question is: Why not? David Ignatius offers some explanations here.