So he got there in the end. You don't have to be a swivel-eyed conspiracy theorist to think that David Cameron was bound to be Prime Minister one day. Of course, his intelligence and upbringing in greenest, most comfortable Berkshire meant he was better placed than most to get where he wanted. And his family history, with a line of Tory MPs on his mother's side stretching back generations, gave him an implicit Conservatism and a freedom to be pragmatic that his more doctrinaire contemporaries found enviable.
He impressed contemporaries when he arrived in the Conservative Research department in 1988. In researching our biography of him, Francis Elliott and I found the words that became almost a cliché among those who knew him then: "destined for great things".
But he is no accidental politician. He had to want it, and, boy, did he want it. It is possible to construct a theory – unproven, I'd say – that he decided in his early teens that he wanted to be Prime Minister. Friends recall the alarmingly self-confident young man sitting at the breakfast table, proudly announcing that one day he would lead the Conservative Party. At Eton, he was quite unintimidated by arriving at this vast and forbidding school.
He was confident to the verge of bumptiousness, contemporaries recall. He failed to get into Pop, the school's set of prefects, and the fear of failure to which he admits may stem from not clearing this hurdle. But contemporaries also remember him in his early years there as a good-natured and amusing boy who didn't stand out in any way.
After O-levels, though, he took off. He has spoken recently of how his near-expulsion from the school for smoking cannabis shook him up.
That episode disappointed his parents hugely, and, duly honouring his mother and father, he took the message on board. When he began studying politics at A-level, it was the making of him. But was he really planning to be Prime Minister even then? His former headmaster Eric Anderson defends the young Cameron, saying that when he – Anderson – was 14 he wanted to play rugby for Scotland, but that didn't mean there was the faintest prospect of it happening.
One exact contemporary says: "Dave Cameron was a complete non-entity at school." But another boy at the school – and one who knew him rather better – says he recalls a conversation between friends, when looking up at the busts of former pupils who had gone on to become Prime Minister, when he and his friends had speculated as to which of their year might emulate the Pitts, Wellington and Gladstone. "I think the only one who might is Dave Cameron," said the boy, to some surprise.
John Clarke, who taught Cameron politics as he prepared for entrance to Oxford, says: "He was very much a late developer academically, one who came good once he did a series of subjects that suited him. He didn't make a great splash at Eton, but, of all the people I taught, he was one of the most impressive.
"I'm pretty sure I viewed him as politically ambitious even then. He was articulate and politically motivated and interested. He was interested in the business of politics, in politics as a profession, even at that stage. I don't think he'd planned it out in the way Heseltine is supposed to have done. He found politics stimulating, in a good pragmatic Conservative way.
"He was intrigued by politics as an art, as a way of resolving problems."
Another teacher, Andrew Gailey, identifies a trend among academic late-developers. "People who do that," he says, "although they grow in confidence more and more, they are never as confident as those who have started at the top. And there's a sense in which he has always wanted to push himself and test himself more, not waste his time.
"He was able and ambitious, in a proper sense, but he was not one of those who was academically self-confident. There was a sense of him wanting to prove himself to himself." This may have been the result of him following three years behind a starry brother who excelled both intellectually and on the playing field. Excel he did in no uncertain terms at Oxford, thriving under the supervision of Vernon Bogdanor and the economist Peter Sinclair.
It may disappoint those who wish to ascribe sharp elbows to David Cameron that at Oxford in the mid-1980s he showed scant interest in getting on in university politics, traditionally a breeding ground for future leaders (among them at that time, Labour's Ed Balls and his Tory colleague Michael Gove). Some of his contemporaries felt he was not pulling his weight ideologically – in the Union, for example – when Thatcher came under fire, but, remarkably, he felt no need to prove himself. Despite what some have said, it isn't entirely clear that he had decided he was going into politics, but if he had, few would have guessed it. He worked hard and played hard(ish), but thought student politics was about students pretending to be adults. He, evidently, knew he was an adult.
In any event, he had found what he was good at, a focus for his ambition. And that enthusiasm was compounded by working for his godfather Tim Rathbone, a Tory MP, in the House of Commons during the university holidays. Rathbone's political personality, incidentally, sheds a good deal of light on Cameron's "noblesse oblige, richesse doesn't" background. He was as far from being a Thatcherite as a Tory MP could have been, and numbered the ANC's Oliver Tambo among his friends. If Cameron calls himself a "One Nation" Tory, the chances are he has Tim Rathbone in mind. Tim Rathbone, one imagines, might have been an outrider in any talks with the Liberal Democrats.
In hindsight, Cameron's progress from Oxford to the Conservative Research Department looks like a pre-ordained next step up the Tory hierarchy, but the truth is that he couldn't find a job elsewhere. He applied to various banks, in the hope of making some money before trying his hand at Westminster, but he was turned down. So he joined the CRD, where he teamed up with his intellectual sidekick Steve Hilton and Hilton's (now) wife Rachel Whetstone.
By this time the politics bug was undeniable. He made no secret of wanting to be an MP, and his promise and implicitly political nature picked him out as a man to watch. He worked on John Major's successful election campaign in 1992, and gained Whitehall experience under Norman Lamont and Michael Howard. In the mid-1990s he ceased being a special adviser to work in the real world, but only with a view to equipping himself better to go back into politics.
He told his wife-to-be Samantha that he wanted to be an MP, and that "she must say" if that was going to be a problem. He also resisted attempts – presumably financially generous ones – by his employer at Carlton, Michael Green, to keep him in television.
He was nominated for Stafford in 1997, but failed to win it. Briefly he considered standing as an MEP, but decided it would be an obstacle, not a stepping stone, to Westminster.
He secured the nomination for Witney, in Oxfordshire, a seat which might have been made for him, and was elected in 2001. Not only had it been Douglas Hurd's – so he was able to resume the sort of calming, patrician pastoral care that Hurd had provided – but more recently it had been held by Shaun Woodward, who had scandalised the Cotswolds by defecting to Labour. Any real Tory would have been welcome after him, but one of Cameron's evident constancy and public-spiritedness was taken to their bosom. Dave has always been good at reassurance.
His party, though, was in the wilderness. William Hague, Iain Duncan Smith and then Michael Howard failed to dislodge Tony Blair. Cameron, a political anorak as much as a tribal Tory, studied Blair's how-to-do-it book.
With Steve Hilton, they devised a strategy for Downing Street, but first, as the jargon has it, they had to earn permission to be heard. Too many people thought the Tories remained toxic. Blair had achieved a political hegemony. Britain was becoming more middle-class, and more social democratic. What need did it have for the Europe-obsessed, ageing Conservatives? Capitalism had won the Cold War, and a New Labour-managed, softened-edges version of it, with appropriate levels of social care, made the Tories look redundant.
The fact that Cameron has overcome all that to reach Downing Street is remarkable.
For some weary souls, whether from the right or the left, his arrival marks the inevitable swing of the pendulum, hung parliaments notwithstanding. A tired government, lacking the Blair lustre, is given its cards after 13 years. Setting aside the historic hiccup of the last six days, it's a return to the throw-the-rascals-out form book. Thanks very much, we'll try the other lot now. According to this view, David Cameron is in the right place at the right time (as the rich tend to be).
But, five years ago, the Tories were on the brink of choosing David Davis as their leader. The "modernisers" were represented by Michael Portillo and George Osborne, and the party showed little real interest in making the changes necessary to do what it needed. Yet Cameron emerged from the pack, overtook George Osborne, got on his bike (a wheeze Osborne had thought of first) and stormed to the leadership.
Most remarkable of all, he managed to remain Osborne's friend, testament to the human qualities that Cameron will need in the job. While much of his life has been striving towards the top job, now that he's there he may find it easier than, say, being Leader of the Opposition, even without a decent majority. While the last five years have involved constant attempts to harry the Government and keep his party interesting and newsworthy, now the world will come to him.
But with so thin a mandate, those personal skills will be essential. As well as the conventional political gifts, his extraordinary capacity for remembering names, his exceptional manners and "the little things" so valued by his parents will be key assets in the parliamentary battles to come. He should not need to be reminded of that, but a good many of his backbenchers – already unhappy about some of the gimmicks – will tell you that, while his ambition to get to the top has not produced a trail of corpses, it has left a lot of ruffled feathers.
At times he has simply forgotten the niceties, and allowed a perception of a remote public school clique at the top of the party to grow. There were occasions earlier this year when a bunker mentality infected those around him, and he has allowed too many competing voices to muddle the chain of command. With an entire mandarin class thrown into the mix, Whitehall will make interesting watching.
He has said for the last year that there was not an ounce of complacency about the election result, and he would tell friends that such-and-such a piece of bad news for his party was a positive "because it stops my lot getting complacent". But the belief that he was taking his backbenchers for granted suggests otherwise. He wasn't massaging the tearooms as he should have been, and the omission was all the worse, they would say, "because it's not as if he doesn't know better".
But he is good at learning. He will take the criticisms on board, as he will have to. In some areas he is surprisingly thin-skinned, but, if leadership is a quality, he has it in spades. As his former teacher Andrew Gailey puts it, "There is a mindset which is crucial to all winners which is the ability to think of what is to come, not what has just passed – to be able to move on." That ability to make decisions confidently was also possessed by Tony Blair, and look how long he lasted.
James Hanning is deputy editor of 'The Independent on Sunday' and co-author, with Francis Elliott, of 'Cameron: The Rise of the New Conservative' (Fourth Estate)
David Cameron in brief
Born: 9 October 1966
Family married to Samantha Cameron since 1996, one daughter, one surviving son. They are expecting another child in September.
Education Heatherdown Preparatory School; Eton; Brasenose College, Oxford.
Early work experience Included working as a researcher for Tim Rathbone MP (his godfather).
Pre-parliamentary career: worked for the Conservative Research Department, 1988-93. Sent to Downing Street to brief John Major for PMQs from 1991 and, from 1992, for general election press conferences. Was working as a special adviser to Norman Lamont, the Chancellor at the time of Black Wednesday (1992). Also worked for Michael Howard when he was Home Secretary.
* Director of corporate affairs at Carlton Communications, 1994-2001.
* Elected Conservative MP for Witney on 7 June 2001.
* In Parliament, served as a member of the Commons Home Affairs Select Committee. Invited to coach Iain Duncan Smith for PMQs in 2002.
* Became a vice-chairman of the Conservative Party in November 2003 and appointed local government spokesman in 2004, before promotion into the Shadow Cabinet as head of policy co-ordination. Later became shadow Education Secretary in the post-election reshuffle.
* Elected leader of the Conservative Party on 6 December 2005.
In his own words...
"I am Conservative to the core of my being, as those who know me best will testify."
On his politics
"I joined this party because I believe in freedom. We are the only party believing that if you give people freedom and responsibility, they will grow stronger and society will grow stronger."
"I think it was right to remove Saddam Hussein... it was the right decision then and I still think it was right now."
On his destiny
"I am the heir to Blair."
On Tony Blair
"He was the future once."
On his party
"We will reflect the country we aspire to govern, and the sound of modern Britain is a complex harmony, not a male voice choir."
On allegations of drug-taking in his youth
"I did lots of things before I came into politics which I shouldn't have done. We all did."
On Gordon Brown
"The character of his government – secretive, power-hoarding, controlling – is his character.... For the health of our democracy it is now essential that this shameless defender of the old elite goes as soon as possible."
What others say
"The more he talks, the less he says." (Gordon Brown) "An actor who has never had a proper job" (Tam Dalyell)