Forget rioters, gangs and drug dealers. There is a far more chilling threat to our streets - and David Cameron hasn't even acknowledged it.
Thankfully, one politician has at last had the courage to speak up. She is Joy Garner, a Labour councillor in Stoke-on-Trent. This morning, at a Q&A session on crime held in London by Ed Miliband, Cllr Garner broached the subject that others seem determined to ignore. She was prompted by Coalition plans to outsource more policing services.
"Building on the G4S thing," she began, gravely. "The RoboCop films are an extreme example of where privatisation can go madly wrong. This just seems to be the first step."
Yes, you read that right. "The RoboCop films." "Privatisation." "Madly wrong." "The first step." Finally: someone in politics has identified the inevitable consequence of getting private firms to manage public services. Namely, that Britain will be overrun by killer cyborgs.
Cllr Garner is no fool. She has seen the investigative documentaries RoboCop, RoboCop 2 and RoboCop 3, and absorbed their key lesson: that we are just years away from finding ourselves at the mercy of wildly unpredictable law-enforcement androids that have machine guns for hands, and aren't very good at descending stairs.
"I think it's very important," concluded Cllr Garner, "to have a framework in place to stop G4S." The public must hope that the Coalition - which remains unaccountably silent on this topic - heeds her warning, before families from Dudley to Dundee are obliterated by 10ft robots that their human masters cannot control.
As ever, of course, there will be cynics. "What a stack of scaremongering, Loony Left cobblers," they will scoff. "The RoboCop films weren't documentaries. They were a hammy Hollywood action-movie franchise from the late 1980s. Privatisation will no more bring about the events of RoboCop than it will bring about the events of Avatar, Jurassic Park or Nutty Professor II: The Klumps."
Will senior politicians rise above such jeering? It remains to be seen. When Mr Miliband and Yvette Cooper, the Shadow Home Secretary, answered Cllr Garner, they neglected to give their views on the prospect of cyborg dystopia. It was almost as though they were sidestepping the RoboCop issue altogether. Instead they waffled about "effective partnerships" and "safeguards". As if mere "safeguards" will protect innocent citizens from a blizzard of bullets unleashed by rogue security-droids.
Mr Miliband seemed more concerned with his plan for "restorative policing". This, he explained, means "forcing offenders to make good on what they've done". So if a thief smashes your window, the thief must fix it. If a vandal wrecks your garden, the vandal must replant it. If a mugger breaks your arm, the mugger must operate on it. That sort of thing.
But, even if her party leader shies away from the big issue, Cllr Garner will not. In November she hopes to become Staffordshire's first elected Police Commissioner. If anyone can save the good people of Tamworth, Uttoxeter and Hednesford from the rise of the killing machines, it's her.