He spoke as a man on the edge of history rather than as someone who has already made it. The Coalition he leads is about to announce the biggest cuts in public spending ever imposed by a government. But the argument he advanced as a prelude was the same one he has been advancing for several years, the same one he advanced in opposition: the argument for a smaller state and big society.
David Cameron addressed his party's conference for the first time as Prime Minister. His party had almost won an election, but not quite. He was working in formal partnership with the Liberal Democrats, a ground-breaking arrangement. But the only context that mattered was that he spoke as a prelude to the spending review and a policy revolution.
The slogan behind him as he spoke was "Together in the National Interest". The words were not only a reference to the two parties that formed the Coalition. They are a summary of Cameron's political philosophy. Governments cannot solve problems, but people can. Towards the end of his speech, he declared: "It takes two to build that big society." He was not referring to the Liberal Democrats but to the rest of the country. "Your country needs you," he declared, melodramatically. Or, as he put it more deftly in his very first speech as Conservative leader in 2005: "There is such a thing as society. It is not the same as the state." No one can accuse Cameron of inconsistency of overriding vision, even if he has flipped and flopped over specific, key policies.
Some of his internal critics argue with a hint of disdain that the "big society" was a misjudged theme at the last election. Cameron showed what he thought of them by moving the theme even further to the centre of the stage. The big society got more mentions in this speech than in any delivered before the election or during the campaign. He believes in it and so do those who work closest with him.
Cameron described the vision as the "beating, radical heart" of the Coalition. He hailed a radical shift in power in which nurses formed co-operatives, parents set up schools and GPs ran the NHS. For Cameron, centrally-determined targets stifled initiative; public spending was often wasteful; bureaucrats got in the way. The new Prime Minster supports citizenship as an alternative to the state. Whether many citizens have the time or inclination to respond, and whether they do so across the country, are two tests of many as the state takes a big step back.
For Cameron, the broader arguments are easier to make at this early stage of his prime ministerial career. His government has not yet made its key moves. The comprehensive spending review, to be unveiled later this month, has overshadowed the conference and was the backdrop to his speech. With justification, Cameron insisted his vision was in place long before the financial crisis; he has not adopted it to justify the spending cuts. Even so, the cuts will test his vision. As Oliver Letwin put it at The Independent's fringe meeting, the Coalition would have welcomed more money to "oil the wheels" of the sweeping changes it is about to make. Instead, the cuts are bound to determine the nature of the change.
All this lent a quiet drama to what might otherwise have felt like rather a flat speech – a sense that something big was about to happen. The first half of Cameron's address was more solidly argued because it was largely based on what had happened, rather than what might happen if citizens become more active in local communities.
He captured well the drama of the Coalition's formation, how he awoke in the morning after the election and decided to make a bid for a formal Coalition with Nick Clegg. He deployed humour to convey reassuring distance, telling delegates that when he gave Clegg his view of the European Parliament, the Liberal Democrat leader said: "It's even worse than I thought".
Cameron's audience cheered most enthusiastically with his attacks on Labour, although he sensibly made virtually no reference to Ed Miliband, an opponent who has been leader for less than a fortnight.
The Prime Minister made only a passing reference to the row over the targeting of child benefits. Here was an example of a specific cut that alarmed activists at the conference and some mighty newspapers. There are strong arguments in favour of targeting, but they were not advanced before the policy was announced. Instead, Cameron and his Chancellor, George Osborne, continue to reveal dramatic policies with the casual inconsistency that marked their spell in opposition.
They have not learnt that the ground has to be cleared in advance of an announcement and detailed work carried out to assess precisely how a policy will work. They like getting headlines, but implementing policy is arduous and fraught. They are inexperienced policymakers embarking on a policy revolution.
As the spending review hovers, the Tories have become sudden converts to the importance of public spending, the illuminating revelation of the conference. Faced with the reality of precise cuts, they do not like them. Boris Johnson, Iain Duncan Smith, Liam Fox and an array of other prominent figures put the case for the virtues of public investment as the axe looms.
But in advance of the axe, Cameron was free still to put his case for a new quality of life with less interference from the centre. What if some of the targets set by the centre did lift standards? What if some of the money deemed as wasteful improved public services?
At the moment, the last Labour government stands condemned. But now Cameron sets out on his journey. His ideas, expressed with persistent eloquence for five years, are to be tested by implementation. In different forms, he has delivered this speech many times. He cannot do so again. Next year, he will need to justify what has happened, rather than look ahead to what might. We are only a fortnight away from an historic announcement on public spending. Cameron's big society might have been envisaged before the cuts but they make its successful realisation more urgent.