Time after time, when there is a chance to give us a leg-up, promises turn to dust when the mortgage statement or payslip arrives, as the 10 per cent tax rate debacle proved.

The number of children living in poverty has gone up by 100,000 for two years in a row, and New Labour's pledge to halve child poverty by 2010 now looks completely unattainable.

Surely, if a Labour government does nothing else, it should help those who are less well-off. But rather than eradicate financial hardship, the very poor have got poorer, while the rest of us, bar the increasingly protected super-rich, are squeezed ever tighter.

Talk about "from cradle to grave" – on the same day that the child poverty figures came out, an official report showed that the number of pensioners living in poverty has risen for the first time in eight years. There are now 2.1 million OAPs in Britain classed as suffering from severe financial hardship – up 200,000 in a year.

I heard a young father being interviewed on the radio. He had a regular job, working in a bar but not earning much above the minimum wage, and he was in a steady relationship with the mother of his baby. A hard-working family, in other words.

But they reckoned that they would be much better off financially if they were to pretend to split up, and for his partner to go off and live as a single mother with the child, taking a "family income" from state benefits.

How can a relationship like that, by no means unique, contribute to the ethos of strong families doing their best to stick together and bring up their children, that ministers are so keen to promote? What would you prioritise? Money for food or daddy around to read a bedtime story every night?

So much for the billions and billions which have been pumped into Gordon Brown's hideously complex tax credits system. How can Britain sustain an economy in which parents who go out to work still end up in poverty while frightening numbers of people remain funded entirely on benefits? Millions don't want hand-outs, they want a way to help themselves, and the current system is not delivering.

I'm sorry, but I don't think Gordon Brown and Co have got under the skin of how serious and endemic these problems are. If the Prime Minister wants to address why so many of our sons and daughters end up with liver failure from binge-drinking, he should get to grips with these economic effects instead of getting Dawn Primarolo to drone on about units. These kids drink to excess because they feel let down, that there is no hope and no viable alternative to a life on benefits, eking out their pennies to pay for six cans of supermarket lager. Ms Primarolo can plead with them all she likes, but it won't make them stop to read the warnings.

I know we had it tough in the 1980s and early 1990s. But those who lost their jobs then, or saw their houses fall into negative equity, or found their businesses crippled by interest rates, had never been promised the land of milk and honey by New Labour. Prosperity for all who played by the rules was the mantra.

One of the most memorable times the now-dread phrase "hard-working families" was used by Tony Blair was in a speech in January 2005 to launch his third-term campaign.

Reading it now, it is impossible to ignore the prophecy buried beneath the slick delivery. "Yes, we have economic stability," Blair said, "but people still work very hard and often long hours to keep home and family together and the economy and job market keep changing…"

If only we had known then what we do now. We were already stretched to the limit, but blithely, few of us realised it. Now with housing costs, interest rates and fuel and food bills soaring, we are all in trouble.

You have to wonder if there is any hope? It sounds like there could be, for the poorest families at least, but it is a case of too little, too late. Alistair Darling pulled together £1bn in the last Budget to increase tax credits and other benefits, with the aim of lifting 500,000 children out of poverty within the next few years. It is also reported that a new inter-departmental ministerial unit has been set up to promote joined-up thinking on hardship. But it is obvious that fresh root-and-branch ideas are needed, and quick.

Instead of endlessly parading his family, and attempting to score cheap political points off Gordon Brown because he
won't do the same, David Cameron ought to seize the moment. He needs to stop going on about his own kids, and to start setting out, in far greater detail, how he will help all those other kids, and the families he professes to care so deeply about, to help themselves.