The Mandelson I knew had a fatal flaw: he was a machiavellian who always cast himself as a victim | Andy McSmith

Others will be shocked by his sleazy, self-regarding disloyalty and apparent lack of concern for Jeffrey Epstein’s victims, but something that will puzzle people who knew Peter Mandelson is: how could he be so stupid?

Should you be thinking of stabbing a colleague in the back, and betraying your country, your government and your party – to paraphrase the prime minister – a basic precaution is not to leave an email trail. During the 2008 expenses scandal, it was the MPs who left proof of their dishonesty in emails who went to jail. I suspect many others got away with it for want of written evidence. You might think a politician so deviously clever that they call him the Prince of Darkness would know that, and not end up with police searching two of his houses.

And any sensible adult knows that lying during a job interview is not only dishonest, but can blow up in your face – yet, according to Keir Starmer, Mandelson “lied repeatedly” to secure that post as UK ambassador in Washington. Furthermore, if you are freeloading off a manipulative sleazebag, it is better not to wander about his house in your underpants, in case there are hidden cameras. And yet this highly intelligent political operator created a trove of self-incriminating evidence and left it all in the care of a convicted paedophile.

When I worked alongside Mandelson 40 years ago, he had one of the sharpest minds I have ever come across. The Labour party was still reeling from a catastrophic general election when he took over as its director of communications on his 32nd birthday. It was dominated by trade unions. It looked out of date and steeped in industrial conflict. Its communications strategy amounted to little more than announcing policies via press releases, and hoping the voters appreciated them.

Mandelson understood that making promises does not win votes if the voters do not trust you. The party needed a drastic visual makeover. Under his supervision, it gained a shadow communications agency, a team of advertisers and other professionals who gave their services for free; it used focus groups to test which messages actually resonated with the public, the party’s red flag logo was scrapped in favour of a red rose, and press conferences were staged in front of soft pastel colours. There was a celebrated party political broadcast, directed by Hugh Hudson, which contained no policies but projected the leader, Neil Kinnock, as someone the voters could trust.

He was very valuable to those he served, most notably to Tony Blair. Starmer obviously thought he would be equally valuable promoting the UK’s interests in Washington.

In retrospect, his fatal character flaws were apparent even in those early days. He could not resist playing power games, using his influence to undermine those who had crossed him. This made him deeply distrusted and disliked. The late Tessa Jowell told me that after Mandelson’s election to parliament, in 1992, he was sitting alone on the green benches when another Labour MP came in and ostentatiously refused to go near him, saying, loudly enough for Mandelson to hear: “I don’t want to sit next to the most hated man in the Labour party.”

One way to react on hearing a comment like that is to take stock, work out what you are doing wrong, and change your ways. Sometimes, Mandelson seemed to try. He declared once that he didn’t want to be known as a spin doctor any more, but the lure of secret power always seemed to pull him back.

It appears to be a common fault of people who live by plotting and manoeuvring that they assume that everyone else is up to the same tricks. Every major setback in Mandelson’s bumpy career came about when a dubious association he had formed with someone rich came to light. His first resignation from the cabinet was over a secret loan from a wealthy Labour MP. The second was over a favour he did for an Indian billionaire. He also attracted a slew of bad headlines after sunning himself on a luxury yacht belonging to Oleg Deripaska, a Russian oligarch now sanctioned by the UK government. Each disaster was his own fault, but not in his own mind. Anyone interested can watch his acceptance speech after he was re-elected MP for Hartlepool in 2001, in which he memorably declared that he was “a fighter not a quitter”. It was a denunciation of those who had “underestimated” him. The fury with which he spat out the word “quitter” suggests to me that, in his mind, he was a wronged man – a victim. I believe he always felt like a victim, and as a victim felt he deserved to be recompensed by all the good things that rich men’s money can buy.

I was never his favourite colleague; nor his favourite journalist after I switched careers. He told a fellow writer on the Observer that I was “one of the most biased, ill-informed, malicious and unpleasant journalists in Westminster”, which his hearer, Barry Hugill, noted down, and showed me the next day. I was rather flattered.

He was, briefly, a non-executive director of the company that owned the Independent titles, and used that sinecure to organise a meeting of the company’s chief executive and the editors of both titles, and me, while I was political editor of the Independent on Sunday (IoS), because I was not providing the coverage that he thought he deserved. Everything that I had written about him was a gentle breeze compared with the tornado that has hit him this week, but he believed I was working with his enemies, and he expected the management to tell me to desist. As he realised that the meeting was not going his way, he became very emotional; he insulted the editor of the IoS, and sounded like a child having a tantrum because he was not getting what he wanted.

I am embarrassed to admit that I sometimes felt sorry for him, because there can’t be much joy inside a mental world in which you are always the victim of other schemers, and never get the recognition you crave. I surmise that the soon-to-be ex-Lord Mandelson is feeling very sorry for himself right now. But he is not the victim in this story, of course. The victims are poor, dead Virginia Giuffre and the other women and girls who were trafficked and abused by Epstein and his associates. Mandelson is a clumsy machiavellian who brought disaster on himself.

• Andy McSmith was chief press officer for the Labour party in the 1980s, and spent almost 30 years as a political journalist based in the House of Commons. His latest book, Strange People I Have Known, includes a chapter on Peter Mandelson