When the Law of Attraction is seeming to bring about the worst of circumstances, is the actual mechanism really the vulnerability of repeated victims being sensed and acted on, because the world is so full of corrupted people who are primed to seek an outlet for dark impulses, including carelessness, thoughtlessness, selfishness, etc.

This is a perfect description of the energetic complementarity we were just describing - that like seeks like - in the sense of being a fit, in the matter of a key and a lock.  It is not that the energies are identical, they are complementary in fitting what they belong with, to satisfy the imbalance in energy in some fashion. While the meeting up of perpetrator and victim causes harm, that creates further karmic damage and carries forward energetically to both parties to bring them greater disarray and a consequence that may grow over time in severity. For the moment, it is answering the call of energy to seek its match. And by match, we do not mean something identical, but something that serves to allow an expression or implementation in interacting.