The hard right and the extreme left have a history of public unrest on the continent which is mostly absent from the UK (Northern Ireland excepted). British youths riot simply because they can, because they are angry, because they are bored, because many of them are feral, raised by dysfunctional parents, because they have no work and no prospects for their future. In order to stand up and support society you actually have to have a stake in that society. These rioting youths, many of them barely teenagers, just don't care if they get caught. Threats by Prime Minister David Cameron to get tough are meaningless to such children. There is nothing the authorities can possible do to them which is worse than what they have already experienced in life.