The puzzles suggest that the strategic model is flawed in one of two ways: either terrorist are irrational people who minimize their utility or the model misspecifies their incentive structure. Psychiatric studies reveal that terrorists are not irrational. This implies that the foremost objective of terrorism may not be to achieve their organization's political platform.
I've always wondered why terrorists would engage in terrorism when it doesn't seem to be effective. I oversimplify, but Abrams's thesis is that terrorists engage in terrorism out of a search for fraternity within the organization. Given the numerous tales of soldiers who are lifelong best friends, this makes sense. Except, of course, that the terrorists are intentionally killing innocent civilians in an attempt to escape their outsider status and achieve a type of insider status within the group.