Last week Gordon Brown claimed that his budget was a mighty step forward in the war against child poverty, but in truth the real war that is being waged by this government is against the family. It is nothing less than the dismantling of family life that is being financed.

Certainly Tony Blair swept to power 10 years ago on an extraordinary utopian vision: the eradication of child poverty within a generation. For nearly a decade Labour has tried to solve the problem by the simple expedient of getting mothers back to work — single mothers, in particular, since child poverty, so runs the fashionable thinking, is particularly associated with lone parenthood.

In his budget last week, as in previous ones, Brown again raised working tax credit to encourage single parents into work. It’s a staggering realisation: that the income of lone parents has increased five times more than the income of two-parent families since 1997. But just in case single parents don’t all rush back to the office, he also raised child tax credit — which has nothing to do with work — to protect those children from poverty, too. Which, of course, defeats the object of the exercise.

This contradictory policy making has been a feature since 1997. Then fewer than half of lone parents worked in paid jobs. So it was confidently expected that, if they were not being stopped from doing so, 70% of lone parents would eagerly flock back to work. If lone mums worked, they would be wealthier and their children would stop being caught in a poverty trap. Or so ran the theory.

The other leg of the strategy was to build more nurseries, increasing childcare for the underfives, enabling their mothers to stop being a drain on the public purse.

Labour’s reforms have been largely ineffective: there has been an increase of only about 5% in the proportion of lone mothers who work 16 or more hours per week, largely limited to those with one child. On current trends, the target of 70% cannot be reached before 2015, if at all.

Indeed, before so much was stacked on mothers working as the frontline solution to child poverty, some questions should have been asked about the employment potential of these women. Single mothers increasingly represent low ability, poorly educated girls who have never worked and live in social housing. Almost half do not have even a single G grade GCSE. These are not executives set to whizz through the glass ceiling.

As the failure of its policies to push parents back to work became clear, so the government had to raise spending on the lone parents who stayed at home so as to safeguard their children. It was a vicious cycle. By 2004 a nonworking parent with three children saw income rise to £11,000 a year, in addition to housing, free school meals, free prescriptions and so on.

From the outset, what seemed entirely overlooked was that lone parents do not account for most poor children. Many children in two-parent families live in poverty and the poverty rate for these has hardly budged since Labour came to power. In fact, children in a working household make up a slightly higher proportion of those in poverty than in 1997 because most poor children with two parents, or 1.4m out of 2m, have at least one parent in work.

This is where it can clearly be seen that these polices have had the effect of disincentivising the two-parent family — the structure that keeps children safest. A couple with two children need to work 74 hours a week at the minimum wage to clear the poverty line after housing costs; but because of the way the benefits and tax system operates, a lone parent with one child working only 16 hours at the minimum wage is above the threshold.

The bias in the system against two-parent families has sabotaged the campaign to end child poverty. Poetic justice? The real losers are the families who the policy shuns.

A more profound flaw in the government’s policy making is that money alone is not enough. The glue that holds families together is not just money but love and the provision of a stable framework that enables children to feel safe. While policy makers are certain that inequalities in children’s chances are due to poverty, the reality is that we have little evidence on whether children’s lives will improve as a result of giving extra money to their lone parents.

There is a multitude of studies that demonstrate how children raised within an intact marriage are more apt to avoid criminal and psychiatric trouble, achieve more educationally, are unlikely to be homeless or abused and, in turn, will successfully raise the next generation, compared with those reared by single or cohabiting, step or foster parents or in institutions.

Tax credits are running at about £20 billion a year. But is the money buying better kids? Extraordinarily, no investigation into the effect on child outcomes of all the extra expenditure seems to have been undertaken. When Unicef published its comparative assessment of the lives of children earlier this year, it put the UK last; brought down by its poor family relationships, bad behaviour and risky conduct (drug taking, drunkenness, early sex and pregnancy rates, bullying and violence). For the entire spending binge, there are no detectable improvements in social outcomes.

What is certain is that the erosion of family structure, with children more and more born to lone women, often of low ability, who may or may not be in transient relationships with various men, are creating such fragile, feral conditions that child-rearing cannot be adequately accomplished. And this escalating family disintegration is being incentivised by the tax and benefit structure.

The War Between the State and the Family: How Government Divides and Impoverishes, by Patricia Morgan, is published this week by the Institute of Economic Affairs, £10

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