First, the number of Muslim prisoners has risen sixfold over the past 15 years. With more than 4,000 such inmates they make up 70 per cent of prisoners from minority groups. They are mostly of Pakistani descent, and the relative absence of people of subcontinental origin who follow other religions is equally striking.

Secondly, Islamic proselytising is prevalent in our prisons. An outside observer might conclude from the religious literature that he sees there that Britain is more an Islamic than a Christian country. I was often surprised on entering a cell in the prison in which I worked to discover a booklet with a title such as The Basic Teachings of Islam. More often than not, this will be the prisoner’s first experience of reading abstract principles.

Thirdly, prisoners as a group are susceptible to religious conversion. Crime is a young man’s game, and most criminals give up crime in their thirties at the latest. The majority give up spontaneously, without outside influence, but some, often the more intelligent, reflective or questioning among them, are seeking a pretext to do so. Religion provides them with that pretext; and by conversion, they do not feel that they have simply surrendered unconditionally to society, meekly accepting its law-abiding, middle-class norms after years of flouting them. They do not simply slink away from crime, defeated by the system: they have actively chosen a new life.

Islam answers more than one of the needs of such people. Many prisoners prefer life in prison to life outside, which is one motive for recidivism. Prison imposes boundaries on them that they are unable to impose on themselves, and a life without boundaries is a life of torment, it is without form, a void. Islam, with its daily rituals and its list of prohibitions, is ideally suited to those who are seeking to contain their own lives.

It has one other great advantage: it is feared by society at large. By adopting Islam, prisoners are killing two birds with one stone: they are giving themselves boundaries so that they can commit no more crimes — at least of the ordinary kind — and yet do not feel that they have capitulated to the demands of society.

Among the majority of young Muslim men in prison, however, the extent of their secularisation can hardly be exaggerated. The same phenomenon has been noticed in France, where a much higher proportion of the prison population — rising to as much as 60 per cent — is Muslim. The prisoners do not pray or keep Ramadan, or perform any other religious duties. Like their white and black counterparts, they are interested in sex, drugs and rock’n’roll. Their one difference is that, thanks to their cultural inheritance, their abuse of women is systematic rather than unsystematic as it is with the whites and blacks. And that is the way they intend to keep it, for it is a very gratifying system to them. That in my view accounts for much of their residual Muslim feeling.

For the reasons I have given, a small number among them, as well as among others, will be susceptible to conversion. And, as everyone knows, the zeal of converts is usually greater than the zeal of those who never needed to be converted or reconverted.

There is one final factor: the match that puts the flame to the combustible mixture is a general sense of grievance and of a grave injustice that they believe has been done them. By injustice they do not mean that they did not do what they were accused of having done. On the contrary, they know perfectly well that, like most other prisoners, they have committed between five and fifteen times more crimes than they have been accused of, and indeed celebrate the fact as a great accomplishment.

No, by injustice they mean social injustice, the opposite of what is called social justice. It has nothing to do with an individual getting his deserts for his own actions. Their justice is an ideal state of affairs, as impossible of realisation as of definition, but which includes an effortlessly acquired, endless supply of women and BMWs. Much religious zealotry is, in effect, disappointed and embittered materialism.

The politico-religious fanaticism of which we are rightly afraid is thus not the product of Islam alone, but of an amalgam of Islam with sociological ideas according to which people are victims of structural injustice, of the modern equivalent of djinns such as institutionalised racism.

In an open society such as ours, this way of thinking is a self-fulfilling prophecy, and encloses people in ghettos of their own making. They dwell on what they cannot do rather on what they can, and attribute the obstacles to others. It flatters them with the comforting illusion that all their failures come from outside rather than within.

Those who talk glibly of social justice, without knowing what they mean by it, are — no doubt unwittingly — promoting politico-religious fanaticism almost as surely as hate-filled clerics. If so many people had been persuaded that the fault lies in themselves, not in structural injustice, the clerics would have a much lesser effect. For every weed to grow not the seed alone, but the right soil is necessary.

Theodore Dalrymple is a recently retired prison doctor

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