Assembling a profile continues to elude academics and practioners. There are some useful hints scattered around in the literature, which is what I would class the 'engineers' articles.

What I did find interesting was the description of a prolonged German data mining investigation to identify potential terrorists - which failed. A marked contrast to hunting down the Baader-Meinhof gang in Hamburg in the 1970's, when a data search identified utilities being paid for in cash and swiftly then their hideout(s).

After London and Glasgow attacks by in the 'Doctors Plot' any profile had to consider medical doctors.

davidbfpo