Two quick items:
1- Richard Koenigsberg offers an online publication, Political Violence and the Concept of Collective Psychopathology. Religion is among the factors he addresses in that document.
2- For those of you who are in the Washington, DC, area:
The 20th annual meeting of the Association for the Advancement of Philosophy and Psychiatry is meeting May 3 & 4, 2008, in Washington DC. The theme of the conference is "Political Extremism and Psychopathology". The group will meet at The Fairmont Washington, Executive Forum (2401 M. Street, NW, Washington DC). I am told there is no fee or registration required.
The program is available (pdf file) at http://www3.utsouthwestern.edu/aapp/Political%20Extremism2008.pdf. Several presentations deal with religion's role(s) in political extremism.