It's a risky business, living in an age dominated by iconic images. The burning towers tumbling down, the hostage pleading for his life, the defiantly veiled woman, the little Iraqi boy with his arms blown off, the twisted metal of bombed train carriages. Each image has its own unique context and yet influences how we read other images. We knot images together to tell perilous stories of our time. Sixteen years after an amateur video of a black man being beaten by cops in Los Angeles flickered across our television screens and triggered terrible riots, we recalled the images vividly as we saw CCTV footage last week of a slight black woman surrounded by four burly men and a police dog straining at its leash, being hammered into the ground by blow after blow.
This time the story - featured mainly in this newspaper and in a BBC Newsnight report - was studiously cold-shouldered by most of the mainstream media. Petty crime or terrorism, went the consensus, the police had to get on with the job. Only sensationalists would compare this beating to the infamous Rodney King episode or the 1997 California shooting of Tyisha Miller, a black woman sitting unconscious in her car. A swift burial of the story took place, although the incident itself has gone on to the Independent Police Complaints Commission for investigation.
We can agree that behind each image lies a unique story, and that Rodney King in 1991 and Toni Comer in 2006 should not be folded into the same narrative. We can acknowledge that police officers work in a dangerous job in difficult times and must be in a position to ensure their own safety and that of others. Not every picture of a white police officer forcefully apprehending a black suspect, even one as fragile as Comer, is an iconic image of racism. Indeed, Comer, who was 19 at the time of the incident last July, has herself steadfastly refused to play the so-called race card, and her complaint to the IPCC is of excessive force, not racism. She is not speaking as a "black woman".
Still, it remains difficult to imagine a petite middle-class white woman being beaten like this, or that so shocking an image would be played down by the media. Iconic pictures of white women tend to tell stories of victimisation by vicious crime (Abigail Witchalls) or capture-and-rescue (the photogenic Jessica Lynch, not Shoshana Johnson, the black woman soldier also taken captive in Iraq). When the pictures from Abu Ghraib emerged, the shock of seeing a white woman engaged in torture was diffused by a spurious class logic that dismissed Lynndie England as "white trash".
Ms Comer was drunk, disorderly and culpable of criminal damage. She was also committing that unpardonable female offence, "ball-busting", as she resisted arrest. Perhaps a guy, whether rapist or policeman, has gotta do what a guy's gotta do, including dragging this young woman to the police van with her trousers around her knees, while she, an epilepsy sufferer, flails and foams at the mouth. It is entirely possible, meanwhile, that PC Anthony Mulhall was, in fact, using "approved techniques" and "reasonable force".
Perhaps this is why the image disturbs us. Or ought to. For it is not only that we live in a time when blacks and Asians constitute a disproportionate chunk of the prison population and continue to be criminalised. Or that institutionalised racism in the police has been acknowledged. Perhaps what should really worry us is that we live in a time when the very definition of what constitutes "reasonable" force is expanding rapidly. And that it is taking more and more people into the ambit of gratuitous violence. What might once have been clandestine, off-camera activity, is now rapidly becoming part of the public and the ordinary. Asymmetry - the many against the few, the strong against the weak, the armed against the unarmed - is gaining legitimacy as the norm. In an international frame, it even has a name: "shock and awe".
It is now "reasonable" use of force to shoot an unarmed "Asian-looking" man at an underground station on suspicion. It is reasonable to bomb an entire nation "into the Middle Ages" for harbouring an elusive criminal, for kidnapping a soldier, or on suspicion of possessing weapons of mass destruction; even more reasonable to spend £20bn of public money to refurbish Britain's own WMD arsenal to deter an unspecified future enemy. It is reasonable, as the Baha Mousa case suggests, for the armed forces in Iraq to punch and kick civilians to death, resurrecting stress positions outlawed 35 years ago.
Our desperate times are marked by constant redefinitions of the reasonable and the acceptable. So new police powers are sought and many granted - shoot to kill, detention without charge and sweeping powers of arrest - while crime itself becomes an endlessly elastic category, from the Asbo to prohibitions on "incitement" and "offence". At home, it is those at the bottom or the social ladder, the most easily disenfranchised - black people, the poor, migrants, Muslim communities - who will feel the brunt of the expansion of state powers, or "approved techniques" of force. Abroad it will be a deemed "rogue" state, the international equivalent of an Asbo, a nation likely to be populated by black or brown people but with uppity aspirations to joining the nuclear club. Only the US and Europe, like nice white middle-class people, can be trusted to keep their cool and exercise the most reasonable force at all times. Challenge this and you can expect an equal opportunity thumping.
The pictures from Abu Ghraib disturbed us because they epitomise the moral terrors of asymmetry: the unarmed captive made to crawl naked watched by snarling dogs and laughing soldiers, subjected to all manner of physical and sexual abuse. Then we were told that what we were witnessing was the exception, the work of a few bad apples. We might yet be given the tale of a rogue cop who is the exception to the Sheffield rule. This is the myth we need to question. What should frighten us is not the isolated image and its unique circumstances but the larger story it tells of what has become so acceptable that it is not even newsworthy.
Poor black, Asian and white communities have no stake in defending guns, petty crime, or alcohol and drug abuse in their midst. Indeed, it is they who suffer most directly from the harmful effects of these things and the violence they spawn. But demonising those at the bottom of the lengthening social ladder while the state expands its exercise of force is hardly the answer. What we are witnessing, at home and abroad, is increasing toughness on crimes, real and imagined, with a constant exacerbation of its conditions and causes. We can look away from that CCTV footage now, but don't be shocked or surprised next time some guy gets shot in the underground by an excitable cop, or we help bomb another nation into oblivion. It's all about the exercise of reasonable force.
* Priyamvada Gopal teaches in the English faculty at Cambridge University and is the author of Literary Radicalism in India.