PLOUGHING my way through this, the 600-page, sixth volume of Alastair Campbell’s diaries, I fell to wondering how, half a century hence, the story it tells will be viewed by historians. Certainly, for the Labour Party, which had been in government eight years when Campbell makes his first entry, it was the worst of times.

Though they had won an unprecedented third General Election, the relationship between the Prime Minister Tony Blair and his Chancellor Gordon Brown had deteriorated disastrously and the pair were like fighters snarling and posturing at the weigh-in. Nursing his wrath like a hellfire-and-damnation preacher, Brown, furrowed of brow and near to foaming at the mouth, could not forgive Blair for having reneged on his promise to step aside after two terms and hand over to him the keys to No 10.

This was government at its most spectacularly and damagingly dysfunctional. The two men who had once been so close and had, in the wake of the sudden demise of John Smith, revived a moribund party and invented New Labour, were by 2005 barely civil to one another. Brown had his camp of followers and Blair his. Whatever they were, they were not on the same wavelength. Thus, instead of basking in the glow of another election triumph, they were engrossed in mutual loathing.

Meanwhile Campbell, the people’s PR-man, was no longer in the thick of it. Having done his bit to get Blair re-elected he was determined to take a step back, save his imploding marriage, spend more time with his kids, stave off depression, and see if there was life worth living outside of politics. Come the summer of 2007, however, Blair has finally given way to Brown and Campbell is still struggling to find his own raison d’etre. As he writes in his closing paragraph, with no false modesty, “TB and GB the main guys. Yet I had been so close to one and responsible in part for getting him to accept the other as successor.”

There is no doubt, as I believe future historians will concede, that Campbell’s role during this period was pivotal. Both Brown and Blair sought and valued his advice and by and large it was worth taking. He would have made a feisty MP and a memorable minister. His own failings, addictions and obsessions were manifold and described here and elsewhere with admirable honesty. He is not one of those diarists who is adept at airbrushing his behaviour. One of the soap opera strands of this volume is his relationship with his abrasive wife, Fiona. Their rows are volcanic, stemming usually from Campbell’s inability and unwillingness to distance himself from Westminster. She comes across as unsympathetic and unreasonable. Together they see a shrink, though what benefit they derive from this is debateable.

FOR his part, Campbell is manic and every day is packed with commitments and deadlines and hoops through which he must jump. He runs, cycles, swims, competes in triathlons, often for charity, and is seemingly perpetually in motion. At one point, bizarrely, Brown rings Campbell to ask if he might be interested in becoming editor of The Scotsman. “He said this was meant in a friendly not malevolent way.” How serious Brown was, and what authority he had to make such an offer, is left dangling in the ether. Otherwise, away from government, Campbell gives speeches, writes for any paper that’s willing to offer him a shilling (while always taking a pop at the media), and accepting offers to play the celeb even as he trashes the culture which breeds them.

His hinterland is not broad. Sport is where he finds most respite from the sturm und drang of politics. Ill-advisedly he agrees to go on the Lions rugby tour of New Zealand as a media adviser. As one disapproving hack noted, it was “like hiring the board of BP to perform an oil change on your car”. In the dressing room ahead of one match he gives a pep talk in which he confesses that his knowledge of rugby is not all it might be – which is not what you want to hear when you’re about to face a pack of rabid All Blacks. This book would have been the better for this episode to have been abridged.

The same might be said of a lengthy account of Campbell’s appearance as a player at a celebrity charity football match, in which he captained a team whose luminaries included Diego Maradona and Lothar Matthaus. No-one could make that up. Among Campbell’s special chums is Sir Alex Ferguson who, like the rest of us, wants often to know why TB and GB didn’t get a grip and govern like adults. But theirs was a concrete-clad bubble out of which woods couldn’t be seen for trees. If they had taken the opportunity to take a peek outside, they might have realised that David Cameron, appointed Tory leader in 2005, was a potent threat to Labour.

For all Blair’s fear and loathing of Brown, he rated him far higher than any of the other potential candidates to succeed him. History may show that when the pair worked in concert for the good of the country they made a difference; they were once the best and the brightest. But it will also surely demonstrate that when their partnership imploded it offered an opportunity for Cameron, whose tenure will be best remembered for the catastrophe that is Brexit. And for that it will be hard to forgive them.

From Blair to Brown: Diaries: Volume 6, 2005-2007; by Alastair Campbell is published by Biteback Publishing, priced £25