Pre Crime: Why are we so confident that we can prevent acts of terrible violence?

As politicians and officials in Washington (state) and Arkansas battle over who should have stopped Maurice Clemmons before he apparently shot to death four Washington state police officers outside a strip mall coffee shop near Tacoma last weekend before being shot dead by Seattle police, we can observe a very enduring if not endearing American obsession-- our conviction that we might have stopped the tragedy (read William Yardley's summary of the blame game in the NYTimes).  Clemmons, sent to prison with a hundred year plus term for violent crimes as a teenager, received clemency and parole from then Arkansas governor Mike Huckabee (who made no secret of his religious belief in the possibility of redemption and change).  Both Washington State and Arkansas officials appear to have missed opportunities (in retrospect) to turn up the control pressure on Clemmons.  More should be learned over the next news cycle or two.  

As an overall trait, this American confidence that better technique and method could stop violence is largely admirable, small "d" democratic, and great for the criminal law and policy reform business (which includes fairly or not, academics).  Overall it may make us prone to waves of generally temporary civil liberties destruction in the name of personal security (as we have seen).  My objection, however, is limited to two points.

First, our obsession with the "recidivist".  Once we have sent someone to prison it seems maddening to Americans that we cannot guarantee they will remain tame forever after.  This leads us to keep too many people in prison, for too long (something that this and other recent crimes will only stroke); blind to the fact that the odds of any particular ex-prisoner committing a violent crime are scarcely, if at all, measurably different from other non ex-prisoners with similar demographic circumstances.  Ironically, the one trait that really may help us track future violence--evidence of major mental illness combined with acts of violence--seems to be largely ignored by our criminal justice system (which accords it little measure of mercy or forewarning).

Second, Americans eschew as "welfare" those things that could most efficiently relieve the most predictable violence (such as substantial economic assistance to victims of domestic violence to escape their threatening partners or efforts to embed high-risk teenagers in cuddly but secure extended school programming).