Last week, in the comfortable surroundings of a daytime TV studio, David Cameron buried compassionate conservatism for good.

Once upon a time, when the prime minister was letting sunshine win the day he promised us he was a different kind of Tory. Five years ago as he busied away trying to decontaminate the Tory brand, David Cameron had very clear views about poverty. Indeed he said this; "we need to think of poverty in relative terms...the Conservative Party recognises, will measure and will act on relative poverty."

It wasn't a policy destined to last for long. It seems this was nothing more than a shallow rebranding exercise.

On This Morning last week, rolling the pitch ahead of his chancellor, the volte face came. Relative poverty was out said the prime minister, and over the weekend, both the deputy prime minister and Iain Duncan Smith finished reading the last rites for an agenda on child poverty that not only delivered extraordinary social progress - but which the pair of them once professed to support.

The government is no longer interested in fighting child poverty. They are replacing a commitment to fight child poverty with a commitment to fight the definition of child poverty. Hardly as noble a goal.

Attempting to advance his new argument, Nick Clegg spent a good deal of his Andrew Marr interview this weekend attacking child poverty figures as a 'bit ropey'. Unfortunately, the figures turned out to be the government's own.

The tragedy of this disgraceful repositioning is that we now know all too well how difficult it is to lift the next generation out of poverty.

Back in the mid-90s, the UK had one of the highest child poverty rates in the industrialised world. Last month, IFS research showed that Labour lifted 800,000 children out of poverty over the course of its time in office. Progress that was hard fought indeed.

The government's repositioning wouldn't be so intellectually threadbare if it had not followed so hard on the heels of a simple refusal to make the choices necessary to prioritise tackling child poverty.

This week, those choices came into sharp focus. Following Nick Clegg and George Osborne hasty pre-Budget conference, it was children's tax credits that were singled out for the chop. The effect? The government is now cutting twice as much from children's and working families' tax credits over the course of this Parliament than it is raising in new taxes from bankers. I ask you: what kind of government takes more off children than bankers?

The impact will be to unravel almost all of that hard fought of the last 13 years.

The IFS now estimate announced reforms to personal tax and benefit policy will now increase relative poverty among children by 200,000 in both 2015-16 and 2020-21, and among working-age adults by 200,000 and 400,000 in 2015-16 and 2020-21 respectively.

The poverty increasing effect of other government changes to personal taxes and state benefits will wipe out any positive effects from the introduction of Universal Credit.

Even the Treasury's own figures could not elide the reality. In its distributional analysis of the Autumn Statement measures, the Treasury admitted that as a result of the decisions taken by the government the number of children living in poverty will increase by 100,000 in 2012-13.

I know better than most how hard it is to put together a credible deficit reduction plan in times like these. But the plan Alistair Darling and I produced before the last election would have entailed borrowing some £37 billion less than George Osborne announced last week. Crucially Labour had a different approach. A focus on getting people into jobs. The right balance between tax rises and spending cuts. And most important of all, a concern that social progress was protected.

Over a decade ago, another politician promised voters he would run as a compassionate Conservative. George W. Bush then proceeded with tax cuts that profited the better off, ran up unemployment and presided over a record increase in the number of states handing out food parcels. Now the mask has slipped from David Cameron and George Osborne. They will never look the same to us again.

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