"Anti-terrorist experts" gathered in London to explore "the puzzle that will help us better understand what determines and motivates the actions of individual jihadists:"

One major argument was about the issue of psychological profiling. This seeks to understand the motives of one group of terrorists in order to predict who might be the next....

"I believe the psychological profiling of Islamic terrorists is a complete waste of time," he said.

"It will not work. It means different things to different people and there is the wrong assumption that if we can identify the traits of known terrorists we can move into predictions.

"The terrorists are not a homogenous population and we simply do not understand why some move from legal activities to illegal."

"Too much is based on a limited range of people and we are seeing only the tip of the iceberg...."

"Psychological profiling is beguiling," he said. "Social profiling, looking at the social background, is more useful.

"It's also important to look at the ways in which a person gets drawn into terrorism and from that to develop counter -terrorism strategies. There is an "IED" progression, from involvement to engagement and then, in some, to disengagement from terrorism....

Despite Dr Horgan's comments, there was a good deal of profiling on display at this conference.

Petter Nesser of the Norwegian Defence Research Establishment had analysed the London suicide bombers and came up with a typology, which, he said, provided important lessons.

He identified four types of terrorist in the four young men who blew themselves and others up:

* the entrepreneur
* the protégé
* the misfit
* the drifter. [Link]