On the morning of the Conservatives’ unexpected election victory of 7 May 2015, David Cameron made an impromptu speech to the party workers at CCHQ. It was helpfully leaked almost immediately after he made it, but there was nothing even remotely embarrassing in his address. He said that: “I remember 2010, achieving that dream of getting Labour out and getting the Tories back in and that was amazing. But I think this is the sweetest victory of all.”

Had Cameron known what would happen next, he may have considered this hubristic. Just over a year after taking his party to their first outright majority in a general election since 1992, he resigned after losing the Brexit vote. He broke with tradition by subsequently standing down as an MP, something that only Tony Blair had done recently, amid claims that he did not want to be a “political distraction”. It was speculated as to what he would do next, given that he told shadowy friends that he had “one big job left in him”. Chairman of the IMF? Some sort of major ambassadorial post?

The taint of sleaze has settled over the former PM now, and it’s doubtful that it will ever leave him

It now seems clear, unfortunately, that Cameron’s “big job” was rather less elevated in its ambitions, and that it has destroyed what little remained of his reputation. Despite his accurately forecasting in 2010 that political lobbying was “the next big scandal waiting to happen”, he has been caught up in an embarrassing debacle of his own construction. As a lobbyist and shareholder in the Greensill banking firm, he sought to influence the UK government into keeping the company alive during the Covid-19 crisis with millions of pounds worth of financial support. That he stood to make around $60 million from his shares meant that his motives were, at best, questionable.

Although Cameron has been cleared of any wrongdoing — the Register of Consultant Lobbyists decided that, “Based on detailed information and assurances provided, Mr Cameron’s activities do not fall within the criteria that require registration on the Register of Consultant Lobbyists” — the taint of sleaze has settled over the former PM now, and it’s doubtful that it will ever leave him.

Compared to his former rival Boris Johnson, whose own (admittedly controversial and Covid-blighted) tenure as premier so far is strengthened by a far greater majority than he ever attained, Cameron will slip down the ranks of modern-day prime ministers to be regarded in the same bewildered and dismissive fashion as the likes of Eden, Callaghan and Heath, rather than alongside his idol Tony Blair or the more elevated duo of Churchill and Thatcher. Even his hapless successor Theresa May has won a certain degree of grudging respect for remaining as an MP and opposing her nemesis’ more incompetent flourishes from the backbenches, while Cameron goes on unsuitable desert camping trips with Arab princes. Does he deserve the opprobrium that has been heaped on him, or can he yet redeem himself in the eyes of posterity?

The problem that Cameron always had is that he has been regarded as lightweight, the “essay crisis prime minister” who breezed through his political career with a mixture of charm and common sense, but who was unable to deal with the major political issue of our generation: Brexit. To an extent, this is an unfair criticism. When he became Tory leader in 2005, beating the much-fancied David Davis by a landslide, the Labour hegemony seemed assured, with a still-vital Blair recently having secured his third election majority and Gordon Brown seen as a powerful and highly intelligent politician. Yet he managed to revitalise his party and return them to government less than five years later.

His tenure between 2010 and 2015 was far more successful than the sceptics might have imagined

If Cameron didn’t win a majority in 2010, that partly lay in structural difficulties in the number of seats that the Conservatives had to attain to win a majority of one. But there was also the suspicion — that remains today — that he was happier as PM in a coalition government and that ideologically there was little to separate him and Nick Clegg. Certainly, he seemed more comfortable with such Orange Book Lib Dems as Clegg and David Laws than he ever did with those on the Right of the Conservative party. Yet his tenure between 2010 and 2015 was far more successful than the sceptics might have imagined, with his right-hand man George Osborne sacrificing personal popularity in an attempt to convince the nation that his policies of austerity were a necessary evil in order to get the country back on its feet after Labour’s decade of economic chaos.

It was, of course, an exaggeration, and there was at least some ideological conviction in the zeal with which austerity was pursued. But Cameron’s own charm went a very long way in convincing the electorate that he was, like Blair in his first term, “a pretty straight sort of guy”. The personal tragedy of his losing his son Ivan gave him credibility when it came to the NHS, and he was a vigorous presence at PMQs when he had to be, which earned him the nickname “Flashman” from a Labour Party in deep decline under the half-hearted leadership of Ed Miliband. Cameron championed gay marriage and successfully presented himself as a liberal Conservative of a kind who didn’t care what you got up to in your own home, so long as you paid your taxes. The long-standing rumours about his own drug use as a younger man never did any serious damage to this brand.

Yet his failure to understand the country he governed led to Brexit, not helped by a flawed and unconvincing campaign to remain in the EU, and his subsequent departure. And now, with the latest round of humiliating revelations, David Cameron is seen as yesterday’s man. He will always be seen in the context of the scurrilous rumour that he once inserted his penis into a pig’s mouth at university, and the current headlines of “nose in the trough” write themselves. This may be unfair, and ignores the way in which he took a once-failed Conservative party and reinvented itself as the party of government. But it is hard to feel any great sympathy for him. The “sweetest victory” of less than six years ago now seems, two prime ministers later, as if it came from another world entirely.