The “rally-round-the-flag effect” sparked by the September 11, 2001, attacks on New York and Washington and by President George W. Bush's prompt launching of the War on Terrorism cries out for the kind of timely analysis that political scientists sometimes can provide. A rally effect is the sudden and substantial increase in public approval of the president that occurs in response to certain kinds of dramatic international events involving the United States. The September 11 rally effect is distinctive for at least three reasons. First, of all the recorded rally effects, it is the largest. Bush's approval rating soared in the Gallup Poll from 51% on September 10 to 86% on September 15.The president's approval rating is the percentage of survey respondents who answer “approve” to the question: “Do you approve or disapprove of the job [name] is doing as president?” This 35-point increase nearly doubles the previous record, the 18-point boost triggered by his father's launch of Operation Desert Storm in January 1991. Second, the further increase in Bush's approval rating to 90% on September 22 represents the highest rating ever recorded for a president (Morin 2001). Third, the September 11 rally effect has lasted longer than any in the history of polling. As of November 10, 2002, Bush's approval rating was 68%—22 points below its peak but still much higher than his rating 13 months earlier.