“It is an abiding and indisputable truth”, wrote Tom Johnston in 1946, “that a people which does not understand the past will never comprehend the present nor mould the future”. He was updating the foreword to his classic "History of the Working Classes of Scotland".

For Johnston, the challenge was to counter “drum and trumpet history and ruling caste ancestor worship” with a more realistic understanding of how society had been divided and power held. His own challenge to the system was as a particularly effective Secretary of State for Scotland, during and after the Second World War.

Johnston’s “indisputable truth” is one I revert to often because it can be applied to just about anything. Without a knowledge of the past, current events exist only in isolation. If there is no understanding of the forces that took us to where we are today, for good or ill, they are unlikely to be learned from.

Collective memory used to be stronger and more likely to be handed down from one generation to the next. Now we are flooded with information which also opens the door to disinformation. In politics, there are always vested interests in discrediting what has gone before; particularly if it creates unwelcome contrast with the present.

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We are entering that phase as a General Election approaches and my plea for a little historical understanding hangs on a largely unmarked anniversary. While volumes were written last year to recall Tony Blair leading Labour into government after 18 wilderness years, this month marks the crucial sequel to that event – the Comprehensive Spending Review of July 1998.

It doesn’t, of course, have the same historic ring. There were no cheering crowds in Downing Street or “Portillo Moments” to symbolise the scale of change. Yet it is the Comprehensive Spending Review, presented by Gordon Brown 14 months later, that laid foundations for massive societal change and delivered much that Labour voters aspired to.

This history which now needs to be learned from, as a matter of some urgency, by those who are naïve about the prerequisite for radical change - ie, the gaining of power in order to change anything. There are also a few tips from the past for those who face the same challenge of offering fiscal reassurance while encouraging belief that “things can only get better”.

An unrelenting message about the former without a vision of the latter does not cut it. Labour’s perfectly good policy commitments which have already passed the fiscal tests as well as the alternative priorities that will run through government need to be presented with clarity -  ie, this is what we will do straight away and this is how we will pay for it.”

The extent to which the defining mission of the Blair governments was to attack child poverty is now largely forgotten. Yet a review of how for the Rowntree Foundation and Nuffield Trust found: “It is fair to say that the Labour Government that took office in 1997 took early childhood very seriously – probably more seriously than any previous government in the UK.

“An early cross-departmental spending review specifically focused on services for children aged 0-7 and the subsequent decade saw vastly increased resources and a wealth of policies targeted on pre-school children, including the extension of maternity leave, the development of Sure Start Children’s Centres and the expansion of both nursery education and childcare”.

Where now do we hear anything of that amidst sneers about “New Labour” and its alleged inadequacies? I prefer to think of having taken “early childhood more seriously than any previous government in the UK" and devoting vast resources to delivery. A generation of children, now young adults, benefited whether they know it or not, and the tragedy is that so much progress has been lost.

These aspirations were boldly expressed in 1997 and immediate progress was made in Scotland as elsewhere by shuffling finite resources. I remember for example that we scrapped the Assisted Places Scheme which paid for a small number of state school kids to go to private schools and put it into classroom assistants instead. But it was the 1998 spending review that put serious money behind these priorities.

So what happened between the caution of 1997 and the radicalism of 1998? As it said on the label, there was indeed a Comprehensive Spending Review. Every nook and cranny of public expenditure was explored. As Mr Brown said in his speech presenting the Review’s conclusions to the Commons: “All new resources should be conditional on the implementation of essential reforms: money, but only in return for modernisation”.

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That statement entailed massively increased funding for the NHS and education. Spending on social security increased but not greatly, because so much emphasis was on getting people into work. Since then, we have moved towards a low-pay society with more poverty among the working poor than those on benefit. An incoming Labour government would again be obliged to review every area of spending against outcomes, efficiencies and priorities.

Meanwhile, Labour has to remind a new generation of what it delivered in the past in order to persuade them of what it can offer in the future. If it is never spoken of, it will not be acquired through osmosis. If the Tom Johnston test is to be passed, Labour needs to teach some of its own people, never mind the wider public, what happened 14 months after the General Election of 1997 and the difference it made to millions of lives.

As that Rowntree/Nuffield report said: “Child poverty fell, with particularly strong improvements in households with a child under five… Investments in early childhood have long-lasting rewards, so the full benefits may not yet have been felt.

“All the main political parties now subscribe to the importance of investment in early childhood in reducing inequalities in life chances, and this fact in itself could be considered part of Labour’s legacy”. In other words, things really did get better – much better and never forget it.

Brian Wilson is a former Labour Party politician. He was MP for Cunninghame North from 1987 until 2005 and served as a Minister of State from 1997 to 2003.