Are we barking up the wrong tree?

It has been frustrating to read the various opinions on "why" have so many people attacked schoolchildren in China recently. The predominant rationale is that the assailants are part of a repressive and rapidly changing society, and they attacked vulnerable schoolchildren to vent their pent-up fury against such a society. Specific societal factors cited are massive migration, the widening income gap between the haves and the have-nots, and corrupt officials.

So we are given to understand that "the incidents are reflective of widespread and rising social anxieties and frustrations and tensions in the Chinese society today", or that the "attacks are only the most explosive and brutal symptoms of an increasingly sullen and contentious society".

The commentators wrap their "ad hoc explanations" in convenient hypothesis that suggest societal factors will continue to produce these types of aberrant individuals. Ad hoc explanations neatly accommodate apparent contradictions such as the fact that the assailants came from different economic classes.