Rabbi Jermey Rosen wonders if prison works, that is whether it succeeds in punishing and preventing or reducing crimes and terrorism. He argues that there are two sides of the punishment because punishment may have unforeseen consequences. Sugary excerpt:
On the one hand you have the issue of punishment. What is its function? Is it to penalize, to cure, or to prevent? On the other hand you have the quite different matter of what steps one takes to protect society from antisocial people. Where potential troublemakers are taken off the streets they can do no harm. However, if in taking them off the streets you are, in effect, creating a far larger threat and potentially even more violence, then the cure is worse than the disease.
Yet that is precisely what we are doing. We are, indeed, protecting society by removing drug dealers and violent criminals or suicide bombers. But we may well be creating a spiral of consequences that will make matters far worse in the long run because there is absolutely no evidence whatsoever that incarceration reduces criminality in the punished, if anything the contrary is true.
Prisons are always going to exist because whether they work or not because the issue is about the consequences of punishment, but simply punishment. In other words, society is so obsessed with the idea of punishment crime that it focuses rarely on the issue of rehabilitating criminals because the idea that most if not all criminals are innately bad and thus impossible to rehabilitate is ingrained in the judicial system.