The riots will no doubt cost the country, and by that I mean taxpayers, a lot of money. And we've already had people pontificating on the wider underlying factors that caused the riots. Most of those people will be telling us that the only way to stop this happening again will be to stop the cuts, spend more on services for young people, reform the police and courts, etc etc.
Now, I don't know for sure that they're wrong. I think they probably are wrong but I don't know. No one really knows. But what I also don't know is whether the cost of their cure will be less than the cost of the riots. I highly doubt it will be. And if the prevention is more expensive than the cure why bother with it?