Perhaps we should, in a sense. If we took all violent acts seriously as potentially predictive of escalating violent acts in the future, rather than dealing with them as isolated incidents, maybe we could intervene and prevent many of these events.
Indeed. The accusation that the school covered up his assault to protect his future career in the military sounds like a perfect precursor to this sort of incident. Ignore and cover up violent acts instead of taking them seriously because "boys will be boys" or some other such crap.