It is always scary when you get a peek inside the Prime Minister’s brain. This happened to me towards the fag-end of the last political year when Gordon Brown gathered us together for his final press conference at Downing Street. He looked terrible but, then, it had been a terrible year.

It was late July and at the time, not unlike now, he was choking on the heat and dust of Afghanistan, the latest fiasco in a long year of discontent that had included duck houses, economic meltdown, swine flu, the Gurkhas, Fred the Shred, Hazel Blears’s “rocking the boat” resignation and Jacqui Smith’s bathplug.

Given all of this, the question put to Gordon Brown was almost gentle. “Prime Minister, you have talked about the tough year that you’ve had. One might almost say an annus horribilis. Are you optimistic that the next 12 months are going to be better?” As he heard the words “annus horribilis”, the PM’s eyes widened and his mouth formed into an instant little rosebud, an almost camp moué of surprise. As an expert on Gordon Brown facial expressions, I knew this was genuine. Clearly the idea that this had been his worst ever year in politics was a new concept. I watched his amazement in amazement. It is bad enough to have lived through an annus horribilis — but to not know you have lived through what you have lived through shows a lack of awareness that is almost as horribilis as the year itself.

The PM now put forward an alternative view, a sort of Not The Annus Horribilis Year. It had been, he allowed, a “difficult” year. “We’ve had to make tough decisions and we’ve had to make tough choices.” He recounted his grand successes, which included increased financial liquidity, social care, low-carbon technology, planning regulations, the White Paper on schools, youth employment and nuclear disarmament.

“And it is a difficult year that I think you can see that we are coming through by Building Britain’s Future, taking the decisions for the long term.” At the words “Building Britain’s Future”, I felt the desire to ring the political equivalent of NHS Direct. If our future depends on this document, Gordon’s cobbled-together “strategic plan” for saving the nation from his own rule, things are worse than I thought.

Social care? Low-carbon technology? Suddenly I realised that things were, actually, worse than I had thought. It was denial almost up there with Saddam’s media illusionist, Comical Ali who, while standing on a hotel roof, declared, as Iraqi troops fled for cover behind him: “Baghdad is safe. Don’t believe those liars.”

So Britain is safe. Don’t believe those liars. We are Building Britain’s Future. It was all too revealing. As he returned time and again, like a dog with a bone, to how he’d taken the right decisions, I actually felt a pang of pity. For he doesn’t seem to know that the nub of the problem is his political personality, not his policies. By this I mean his almost visceral need to be right, his obsession with dividing lines, his dogmatism, his endless self-justification and his love of lists. Indeed, I am surprised that he didn't crow: “This is no annus horribilis. What about 1349! That was the Black Death. Or 1536! Henvy VIII had it worse!”

If he can’t see it, everyone else can. For if journalism is the first draft of history then sketchwriting must be at least the first draught and, re-reading my sketches over the year, I could see the cold wind slicing through his premiership. The thing you get in sketches is the detail and, for Gordo, the devil is most certainly there, horns, tail, fork and all.

It is tempting to see this year as an entry in a freak show which, like a Diane Arbus photograph, fascinates even as it repels. But, seen as a whole, a pattern emerges. The recession worked for Gordon for a while but then all that boasting began to grate. Looking back, you can see how Gordon, with his political personality, sowed the seeds of his own destruction. And how David Cameron began to turn it round, using Gordon’s words against him.

So Gordon’s had his annus horribilis. But, worryingly, what we have learnt over the past year is that, as Labour almost sang, things can only get worse or, even more horribilis.

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