Decent People Besieged

Not for the first time I have sat on a case in which shopkeepers, most of them Asian, seem to be living in a state close to siege. In the latest, a normal-looking parade of shops in an otherwise respectable suburb of London is beset by an amorphous group of locals, mostly but not exclusively young, who hang around doing nothing much apart from giggling, shuffling, and leering. These people routinely steal from the shops, intimidating and occasionally assaulting the owners. In evidence, the shopkeeper who had been assaulted said that assault contempt and abuse was just part of running the business, and that when people steal goods his only priority is to get them back. Often, a trader confronting a thief is surrounded by a jeering and threatening mob, and retreat to the store is the only safe option. There is an obvious racial subtext here, based on the loathing felt by the underclass for brown people who have the cheek to work hard in crap jobs in order to get on in life. This loathing does not prevent the oppressors from buying their cans of Tennents from the despised shopkeepers, and the fact that the shops take their cash serves in some way to reinforce an unjustified feeling of superiority to the 'Pakis'.
I am depressed by this, but I am angered more. These shopkeepers feel with some justification that nobody in authority is too bothered by their plight. The police attend when called, but where is the prevention? Where are the patrolling officers who will, by their presence, symbolise society's determination not to allow decent and hard working people to be treated like this? I feel ashamed of the system's failure to protect these people, and I feel humbled by the lack of bitterness they show after near-intolerable treatment.