Is addiction a moral defect, a mental illness or a party trick gone wrong? Two events, a policy and a book, pose the question again. The policy is from Iain Duncan Smith, ever fretting over a vampiric underclass and their disgusting habits. IDS is considering docking the benefits of addicts who decline "help"; it seems they must attend Alcoholics Anonymous (AA) or Narcotics Anonymous (NA), or risk greater poverty and, inevitably, chaos.

This is a tax on mental illness that will apply only to the poor; rich addicts, thankfully, will be left alone. Like many of Duncan Smith's dreams, the fantasy is grandiose and almost an acceptance of the disease model of addiction, if only from small state fetishism. Will we see more evidence of this acceptance in better NHS funding for psychotherapy and rehab, or an acknowledgement that drug and alcohol abuse flourish when there is no work? I doubt it, and in any case, the reality of his policy will be dust in his hands.

As John Sutherland pointed out last week, willingness is essential to recovery, and willingness cannot be bought. Duncan Smith will pay people to go to AA, and AA will be filled with new members who are there because he made them go. This will make for some interesting sharing, but willing members will, in my case with boggling eyes, take responsibility for IDS's victims alongside their own illnesses, signing papers to provide evidence of attendance; imagine a mother and baby group at war. Anonymity, meanwhile, is smashed; it will go down like a Priory made of dominoes. In seeking to soothe addiction, IDS will imperil one of the only known means of arresting it. Wondrous.

And so to the book – The Fix, by Damian Thompson of the Telegraph. It is a strange creature, in part a poison pen letter to AA from a former member. It attacks the disease model of addiction, which has been the accepted dogma for more than 50 years, endorsed by almost every medical authority in America, where most of the research is done – the American Hospital Association, the American Public Health Association, the National Association of Social Workers, the American College of Physicians, the National Institute on Alcohol Abuse and Alcoholism.

For the vast majority of scientists, as Thompson acknowledges, you are no more responsible for being an addict than you are for having leprous limbs, even if this consensus has little impact on social policy where addicts are still treated with contempt. Even so, to dispute it is a popular game among libertarians. Last year the blogger Brendan O'Neill wrote a piece congratulating Amy Winehouse for not being suckered by the therapy industry, even as her ashes were interred in the mud. Thompson's status as an ex-AA member renders The Fix a dangerous polemic that exposes addicts to social censure – a daft fate for sufferers of an illness so intrinsically dependent on self-hatred – and financial and occupational insecurity: it is almost impossible for addicts to be insured, even in 2012.

Thompson's opening passage on alcoholism is anecdotal, brutal, subjective. He describes an AA member – in unflattering terms – who will likely recognise herself. He says the group "seemed almost proud they had this 'disease'" – were they, or weren't they? He insists the members "describe disasters that befall those who stray from the true path [with relish]". Does he relate their testimony from memory, or did he take notes?

Thompson bases his complaint on the stories of two of his friends. Both abused alcohol and drugs: one lived, one threw himself off a building. His conclusion is that, since some addicts recover it cannot be a disease. So what is it? "The behaviour of addicts," he concludes, "looks voluntary because it is … there will always be people who … change their mind and pull themselves out."

What of the science? The most comprehensive study (by George Vaillant at Harvard) suggests that almost no one who drinks alcoholically ever drinks normally again; twin studies suggest addiction is hereditary; A Thomas McLellan's enormous round-up of the data noted "higher rates of dependence among twins than among non-twin siblings and higher rates among monozygotic than dizygotic twins. Evidence," he says, "suggests significant genetic contribution to the risk of addiction comparable to that seen in other chronic illnesses … the choice to try a drug may be voluntary, [but] the effects of the drug can be influenced profoundly by genetic factors."

McLellan admits: "It is not yet possible to explain the physiologic and psychological processes that transform controlled, voluntary use of alcohol and other drugs into uncontrolled, involuntary dependence", and this is the hole that Thompson crawls through. The Fix reads only like bitterness, an unconscious elegy to shame; add Iain Duncan Smith's coerced AA meetings, and fair treatment for addicts feels, as ever, far away.

Twitter: @tanyagold1