You can, it is said, often see someone’s true character when they are under pressure. Challenged by recent months, David Cameron is rolling back the years. Not simply in his frontbench appointments, but in the very essence of his politics. Gone is “progressive conservatism”. The nasty party is on the road to return.

Cameron’s appeal to his party and indeed the electorate was the promise of “decontamination” and an end to the “nasty party”. Out went right-wing postures. In came riding with huskies. But amid a blizzard of photo opportunities came no serious attempt to take on the unreformed instincts or nostrums of his party. For its part, Cameron’s party stopped acting up. It became like a subdued animal. Quiet in the hope of a reward.

Until now. In the face of the market’s global crisis has come the resurfacing of an ideology that Cameron has spent two years trying to bury. It is unclear why he himself chose to dig up this past, but in three big changes Cameron has ditched any pretence to be “heir to Blair” or cousin to Obama. He has left the centre ground, set course for isolation and sought a reunion with the doctrine of self-help.

What’s the evidence? First, let us turn to his do-nothing plan for the downturn. In a seismic shift, the Tory leader has this month decided to come off Labour’s spending plans and cut £5 billion from this year’s budget. At his press conference last week, Cameron tried to duck the big question of whether his cuts plan would actually lower the national debt this year. Answer?

Er, no, it would not. It would leave it the same. Cameron would leave national debt where it is, cut public investment by £5 billion and transfer the money to some savers – an approach that would not reach even 60% of pensioners, the very group the policy was supposed to help.

So, while Labour is offering tax cuts for the vast majority of the British public, value-added tax cuts for all consumers, basic rate tax cuts for 22m basic rate taxpayers and extra help for pensioners and those with children, the Conservatives oppose these measures in favour of offering tax cuts to merely a few. Sound familiar? It is a decision to retreat to an appeal to the core vote.

Second, the Conservatives’ idiosyncratic decision to reject any notion of using extra public investment to give the economy a shot in the arm leaves them alone in the world and dangerously exposed to irrelevance.

This is really important. For a trading nation such as ours, global co-ordination of fiscal action, public investment alongside cuts to interest rates, is absolutely critical to a faster recovery. But how would we persuade other nations to put investment into the world’s economies if we actively opposed such steps at home in a complete rejection of the advice of almost every leading economist? Our arguments for global action would hit a brick wall. Our international leadership would end. And our country would be left to face this international storm alone, our influence on the world stage tragically weakened.

Third, think about the future. Last week Labour published a white paper on how we create the jobs of the future and invest in helping families turn aspiration into success, from early years to professional career development. Aspiration has always united the centre and centre-left in Britain. Our ambition is a revolution in social mobility. It is a plan backed by £10.5 billion of new investment in children, families, skills and communities.

The Conservatives’ reaction? To label our white paper “class war”. Their idea is to cut £200m from Sure Start, £4.5 billion from building schools for the future, to reject plans to give half of kids the chance to go to university and to slice work-training opportunities for a million people a year. This is backed by a promise to cut Labour’s investment plans for the two years ahead. In other words, to cut back on our future potential.

Cameron once presented his brand of philosophy as “rolling forward society”. It was a different intellectual story of conservatism to Margaret Thatcher’s (more Edmund Burke than Milton Friedman) but it had the same ending. Thatcher argued that government action crowded out the market. Answer? Cut back the state. Cameron argued that government action crowded out civic society. Answer? Cut back the state.

I am not surprised to learn that Cameron’s plans draw no distinction between cuts to government and cuts to civic society. The Conservatives’ spending plans would slice a neat 1% off the Cabinet Office budget for supporting the third sector, cutting funds to more than 2,000 small local charities plus 400,000 volunteering opportunities with it. Some “rolling forward”.

Many in the radical centre of British politics were prepared to give Cameron a hearing as he started his task of fashioning “progressive conservatism”. Today we see it as a parody, a showboat. It’s not progressive conservatism, just progressively more confused – for the simple reason that it lacks any anchor in values. With no intelligent account of the market and therefore nothing to say about the future of government. It might be Conservative. But it’s certainly not progressive.

Liam Byrne is chancellor of the Duchy of Lancaster and minister for the Cabinet Office

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