It's fascinating, if disturbing, reading.
Basically (and trying very hard to avoid copyright issues) it argues that the suicide bomber does what they do because of peer pressure - that is, once they have made a pact within the group it is very difficult for any individual within the group to pull out even though they will die in the process.
The article contains reference to Dr. Ariel Merari and his ongoing work into the psychology of the suicide bomber. He appeared before the "Special Oversight Panel on Terrorism" in the US. A transcript of that appearance can be found
More disturbing reading I'm afraid, but relevant.