The Web site run by al-Qaida in Iraq was strangely quiet during the referendum. There were no threats against voters, no boasts of disrupting the vote. And now we know one reason why. Dijana was responsible for much of what has appeared on the Web site called "al-Qaida in Iraq," including provocative videos of suicide bombings and crucial communications to al-Qaida fighters. Here is how the al-Qaida site works: On any given day in any of a dozen cities, a suicide bomb explodes. The target is an American convoy, local Iraqi police or perhaps civilians exiting a mosque. Within minutes,...