Mix violent street disturbances, excitable commentators, angry politicians and "experts" on youth culture and what do you get? Hot air. It is perfectly possible to be horrified by last week's riots without rushing into a moral panic or claiming that they fulfil doomy predictions about the impact of spending cuts. But it is vital to identify the causes, because the response of national politicians, local councils and schools will be shaped by assumptions about why the violence happened. Yet much of what has been said in the past few days has been irrelevant for a simple reason: mobs are not driven by reason.
The looters who smashed windows and torched buildings were in the grip of intense emotions, visibly excited and revelling in the destruction around them. In court, some of the defendants appeared bewildered by their own behaviour. Crowds behave differently from individuals; assuming that looters ransacked shops because they were angry about bankers' bonuses or MPs' expenses is to credit them with conscious processes that don't exist in the heat of the moment.
Violence is exciting. The entertainment industry exploits this with violent films and computer games. When social norms are breached in real life, as they rarely are in peacetime, there will always be a small number who relish the chance to join in. Most of us don't. But young men are particularly susceptible. So far, most defendants passing through the criminal justice system are males under 25. Many are unemployed.
This is fertile territory for moral outrage. A "liberal elite" has been blamed for producing a generation of "feral" kids, a claim as fatuous as some left-wingers' attempts (thankfully reined in by Ed Miliband) to suggest that the riots are down to the withdrawal of the Education Maintenance Allowance. Anyone who robs an injured student has a wonky moral compass, but the destruction on our streets confirms that a substantial minority of kids are growing up without empathy.
Children need to develop a capacity to understand and respect other people's feelings. They need to learn not to over-react when they are disappointed or angry, which isn't easy when parents are absent or distracted by their own problems; some adults are themselves addicted to romance, craving the excitement of short-lived relationships and barely aware of the impact of such instability on children. The red-tops' obsession with celebrity provides terrible models of how to relate to other human beings, while children from poor backgrounds are bombarded with messages about the desirability of brands their families can't afford. They aspire to identities based on crude forms of power, which makes gang membership attractive.
Failure at school and a lack of job prospects make the situation worse, but these people's problems started in infancy. They need substantial intervention to change the habits of a lifetime, and right now, psychology is a better guide to that than politics.