Budgets are never just about the economy. They are major political interventions and the last budget before a general election has to be a showstopper to have any effect on the political weather, especially if your party is lying consistently 20 points behind in the polls.

This one confirmed that the government will stagger on in the hope that its fortunes will look up by October, when I believe it is likely to announce a cut in income tax in a last-gasp pre-election autumn statement. The Sunak administration is destined to go out not with a bang, but a whimper.

The Bill Clinton doctrine – “it’s the economy, stupid” – does tend to hold true in determining the outcome of an election. However, the Thatcherite evangelists who dominate today’s Conservative party are mistaken in taking this to simply mean tax cuts.

The problem they face is that, with real-terms wages below 2008 levels and a cost of living crisis hitting people with increased mortgages or rents and energy and food price rises, a tax or national insurance cut would have to be unaffordably massive to have any meaningful electoral impact. Added to that, a large section of the electorate do not gain any benefit from tax giveaways because they are either non-taxpayers or do not pay national insurance.

That’s why November’s national insurance cut received such a muted response, especially as 40% of the gain goes to the richest 20% and the freezing of tax thresholds yet again wipes out any gain.

Most people now rightly judge that their wellbeing is influenced by more than just their level of taxation. It’s determined just as much by whether they and their family can get treated if sick or have the operation they need, or secure the care for their elderly relatives, or there are enough teachers in their children’s school.

So Hunt’s budget, with its inadequate NHS and schools funding and new round of cuts for councils and social care, is likely to go down at best as irrelevant and more likely as nothing more than the cynical pre-election gaming of a desperate government in its last days, hamstrung by an anachronistic fiscal rule. Many Conservative MPs fighting to hold on to their seats will be asking the question: “Is this all you’ve got?”

t may deliver some positive headlines over the next 24 hours from a few Conservative-allied newspapers and columnists, but it will not frame the election campaign in the way that Rishi Sunak and Hunt hope.

Budgets aren’t just the set of economic decisions contained in the budget documents. Budgets are an expression of the values of the policymakers who write them and the vision they have for society. The most worrying element of this budget is that it betrays the society that modern-day Conservatives are content to maintain.

It is truly shameful that Hunt and Sunak did nothing in the budget to help lift out of poverty the 3.8 million people, including 1 million children, who, according to the Joseph Rowntree Foundation, are now so poor they are destitute.

It says a lot about the lack of compassion in government that this budget has ignored the 8 million adults and 3 million children whom the Food Foundation identifies as experiencing food insecurity – in other words, who don’t know where their next meal is coming from.

With more than 7.6 million outstanding treatments on the NHS waiting list, the failure to provide a truly adequate budget for the NHS will be seen by clinicians and patients as a betrayal of the sick.

As more councils go bust and council taxes rise again, as residential care homes and more Sure Start centres, libraries and arts and sports facilities close, local councillors of all political hues will despair at the impact on their communities of yet another round of cuts to local government financing.

All in all, this budget smacked of a chancellor and a government that knows it’s on its way out. Its exit will be ignominious, as evidenced by Hunt stealing Labour’s non-dom tax policy, which was little more than a puerile display of political game playing.

His projection of another round of budget cuts in most government departments after the election was nothing more than a malevolent attempt to set up the incoming Labour government to fail.

This budget leaves a toxic legacy and poses serious questions for the incoming Labour government. With a sustained 20-point lead in the polls, Labour may not feel it’s necessary or politically wise to try to answer all those questions before the election.

Nevertheless, even if the Labour party can get through an election campaign not answering questions, after the election the question of how to find the resources needed to tackle poverty, rebuild our public services and invest in building a green economy will come rushing headlong at Labour’s Treasury team.

There is a responsibility on all those who want to rebuild our economy and society to be working up their proposals for change now, including their resourcing, and to be building support for these reforms so that it will be easier for Labour to lift them off the shelf when needed in government.

Under Labour, we will have a golden opportunity to ensure budget-making is not about short-term political gain, but an open process, with widespread public engagement of civil society and social movements openly discussing and agreeing the long-term objectives for our economy. We cannot let the first Labour government in 14 long years fail.

• John McDonnell has been the Labour MP for Hayes and Harlington since 1997. He was shadow chancellor from 2015 to 2020