Steve Richards: Why Alan Johnson's letter could deliver the next election to Labour – or to the Tories

The inaccessibility of well-rewarded GPs has become a potentially fatal symbol for the government

A ministerial letter to GPs seems like a tiny pebble in the pond compared with the Northern Rock crisis, missing CDs and the rest. Yet the letter from the Health Secretary, Alan Johnson, suggesting GPs should open their surgeries for a few more hours a week is more important politically than any of the other waves whirling around the Government.

The inaccessibility of well-rewarded GPs has become a potentially fatal symbol for a government vulnerable to claims that it spends a lot of our money and makes virtually no difference to public services. The claims are nonsense and yet potent. If they persist, the Government will lose the next election.

Public services have improved considerably since 1997, but memories are short. Voters have forgotten the rotting schools, non-existent trains and the darkly comical waiting lists for operations that deformed Britain in the 1980s and 1990s. Instead, and sometimes with good cause, they worry about the grim experiences that they suffer now and make comparisons with equivalent countries rather than with Britain's Third World past.

A common anecdote is of British families in Europe needing a GP at the weekend and discovering to their amazement that one is available. It does not take long to recover from the pleasant surprise before an obvious question is asked: "Why can't we get the same service in Britain?" Soon the sequence of thoughts ends with a potentially fatal conclusion for Labour: "This bloody government has wasted our money. Let's give the others a chance."

More than any other innovation, the opportunity to see a GP in the evenings or at weekends would provide a check before the sequence reaches its damning denouement. What is more, Johnson's relatively modest proposal in his letter gives the Government a chance to revisit the scene of its biggest domestic cock-up, the original negotiation of the GPs' contracts.

Although less immediately de-stabilising, the contracts were this government's poll tax. As with Margaret Thatcher's so-called flagship policy from the 1980s, the political stakes could not have been higher. Here was a government bravely putting up taxes to pay for improvements in the NHS. But almost immediately after the tax rise, the attention of Blair and Brown was diverted by an energy-draining row about the powers of foundation hospitals and the fantasy debate about "choice" – a debate conducted as if the NHS had moved with a wave of a wand from squalor to a surplus of good hospitals from which to choose.

While the titans were battling it out, the much more pivotal negotiation of the contracts was left to incompetent health secretaries and their complacently gullible officials, with little public scrutiny and, predictably, no cabinet discussion. Not for the first time, the BMA took the Government for a ride. This was a terrible outcome for a government that had to prove every penny of additional spending was worthwhile in a country brought up on the wholly incorrect, but deeply embedded, assumption that public investment is a waste.

The original negotiations were even more calamitous because those who got the worst deal were the middle income earners who work long hours and pay more taxes. They are the ones who have most difficulty getting to GPs. The retired, those on benefits and the very rich have the time or the means to see doctors when they wish and yet they do not pay the higher taxes. It was those who were paying the GPs through their taxes who could not easily get to see them.

Ever since, senior ministers have been aware that they blew it, but have been wary of taking on the mighty profession. I recall travelling with Tony Blair to Nottingham in his final year as prime minister when he visited Boots and praised the chemist for making services available at times when people could make use of them. He said in passing that he hoped to persuade GPs to do the same. I was the only journalist there and he asked me not to report this comment in case the GPs erupted.

The Government must risk the eruption. Currently, Gordon Brown is getting a lot of advice from left of centre think-tanks and MPs. Quite a lot of it is mischievously simplistic, revolving around the question of whether Labour stands for a big state or an enabling state with few daring to explore what they mean by either proposition. Such superficial introspection will not resonate at the best of times. It will not do so for sure if there is a sense that a government raised billions of pounds and wasted it. A debate over whether the state is enabling or big seems rather peripheral when many cannot see a GP when they want to.

As Johnson returns to the scene of his predecessors' folly, the stakes are high. If he succeeds in getting GPs to open when people can visit, he will show that government is capable of acting constructively on behalf of the tax payer. Such an act of intervention would be more politically useful for Labour than a thousand ultra Blairites railing vaguely against the state, especially as the wider political dynamics are finely balanced.

The Conservatives are gyrating wildly in relation to this theme. Their policy is to spend the fruits of economic growth on spending and tax cuts. Yet they are also committed to sticking to the Government's spending plans, even though there is no scope for tax cuts if the plans are to be met.

Probably, in the current economic climate, the already tight spending limits will be met only as a result of tax rises or additional borrowing.

David Cameron is also under considerable pressure from within his party to scrap altogether his pledge to stick to the Government's spending plans. He would be wise to resist such pressure, but has proved flexible enough on other matters to suggest that he might succumb. Either way, there are tensions and incoherence at the heart of the Tory approach to tax and spend that make them more vulnerable than they seem in the current media-friendly climate.

But the Government will not be in a position to expose the frailties of the Conservatives' approach unless it convinces voters that it can be trusted to invest their money wisely: a daunting challenge after ten years in power and much obviously wasteful spending (but who spends private money without wasting some? None of us).

For a government behind in the polls, this must involve a grown-up narrative that reminds voters what public services were like ten years ago, admissions that mistakes have been made and an explanation that it takes time for the investment to make an impact. Above all, the Government needs urgently to make connections between seemingly distant debates about economic policy and the services received by voters. At the very least, that means GPs opening their surgeries at times when most tax-payers can visit them.

s.richards@independent.co.uk