History, so it is often said, is written by the victors. There seems to be an exception to that rule in the case of Tony Blair. Three consecutive election victories, two of them by landslides, ought to give him a place in the history books as Labour’s most successful leader. He is one of only two prime ministers since the Napoleonic wars to secure an unbroken decade at No 10. The economy grew in every single quarter of his premiership, a record unrivalled by any other major developed country. Sharply higher levels of investment went into health and education, the school and hospital building stock was renewed, child poverty went down and even the Tory party eventually embraced much of a legacy that includes the minimum wage, more spending on international aid, gender equality and gay rights.

When he left office, pollsters reported that a majority of voters thought he had done a good job as prime minister, all in all, and even that he was still “likable”. That’s not bad after a decade at the top. Yet it is now a commonplace of much public discourse that he was one of the most despicable characters ever to inhabit No 10, even the “most hated man in Britain”.

Some of this is his own fault. Even his best friends would acknowledge that he has not been a careful custodian of his post-prime ministerial reputation. At the same time, the right and some strands of the left have seen a self-interest in burying him with odium. Tories find revenge and justification for their current actions in trashing the reputation of the man who locked them out of power for the most extended stretch since the 18th century. Elements of the left, rather perversely, help the Conservatives when they talk as if Labour did nothing worth respecting with its longest span in office.

Tony Blair's A Journey: Andrew Rawnsley's review Read more

Here with the latest contribution to the Blair hate industry is Tom Bower, who has pounded out more than 600 pages of monotonal hostility. I came to this book with considerable admiration for the author. He is a dogged and ballsy investigative journalist who has taken on some highly tricky and litigious subjects like Robert Maxwell and Conrad Black. But I guess there may be a price to pay for making a living from hunting monsters. You end up only being able to see the dark side of anything. In the Bower version of Blair, there is nothing that he has touched that has not been shallow, worthless, dodgy or a deceit.

There are parts of the critique that are fair enough. Blair came to office with much of his agenda for the public services only sketchily thought out. An acrobat politician rather than an engineer politician, he was never sufficiently interested in the mechanics of government and that had consequences for its performance. He should not have tolerated a chancellor who sabotaged him from within, generating an internecine struggle for dominance that began on day one and did not cease until Gordon Brown finally supplanted him.

There is also a familiar ring to Bower’s charges about the Iraq war. In the wake of the terrorist atrocities in New York and Washington, the obsession with staying in lock step with George Bush blinded him to the many hazards of the American adventure. Blair was seduced by MI6, whose boss, Sir Richard Dearlove, over-promised on the agency’s ability to secure reliable intelligence about Saddam Hussein and then delivered material that was bogus or useless. He committed to joining the war long before he told the cabinet or the public, sold the invasion on the basis of a false prospectus about weapons of mass destruction, and the planning for the aftermath was shockingly and catastrophically inadequate.

He never introduces any of the challenges Blair faced when he arrived in office after 18 years of Conservative rule

The problem with the Bower version is that, even when his criticisms might be just, he tells the story in such a relentlessly accusatory tone that he leaves no room for any subtlety or context in his narrative. He never introduces the reader to any of the challenges that Blair faced when he arrived in office after 18 years of Conservative rule and with no previous ministerial experience. Nor does he acknowledge that any British prime minister would have faced an acute dilemma after 9/11 when confronted with an angry US and a president determined to go to war. If you are interested in why Blair made his mistakes, you won’t find any profounder explanation than the repeated assertion that he was a duplicitous and conceited fool. Any deeper inquiry into the personality of one of the more fascinating characters to live at No 10 is dismissed on the grounds that trying to “unravel” Blair is “unsatisfactory”.

Sometimes Bower is straining so hard to damn the accused that the author tumbles into the ridiculous. Several chapters are devoted to trying to sustain the accusation that Blair presided over a “silent conspiracy” to flood Britain with immigrants. Yup. It was so secret that immigration was on the front page of the newspapers most weeks. While Bower presents himself as a detached quester after the truth who approached this subject with unpartisan “curiosity”, he can’t always keep his prejudices under control. Writing about the legislation to control fox hunting, he claims that this represented “Blair’s betrayal of British values” and “middle England”. No, the curbs on the blood sport implemented a manifesto commitment for which middle England had voted.

This book is like attending a show trial at which the only witnesses you ever get to hear are those for the prosecution. If anyone he spoke to had a complimentary word to say about Blair, Bower does not report it. His voices are predominantly drawn from the ranks of disgruntled former civil servants and spleen-venting retired military officers. Their testimony might be more persuasive if any of them were ever prepared to concede to their misjudgments. We might also note that not one of the brass hats and mandarins who now fulminate about Iraq resigned at the time.

Even the most ardent Blair-haters will usually concede he devoted enormous amounts of time to the peace process

What about Northern Ireland? That surely is a bit of a challenge to Bower’s lust to find Blair guilty on all counts. Even the most ardent Blair-haters will usually concede that he devoted commendably enormous amounts of time and energy driving the peace process. On his watch, the IRA, which had been the most murderous killing machine in Europe, put itself out of business. Two communities that had been riven by decades of sectarian conflict agreed to lay aside violence and embrace democratic politics. It was a tribute to Blair’s perseverance, creativity, resilience and talent for persuasion that he induced Ian Paisley, the Dr No of unionism, and Martin McGuinness, the former IRA commander, to govern together. Bower gives a sparse few sentences to Northern Ireland in which he forces himself to acknowledge that Blair had a “success” – but only in order to launch an argument that it deluded the accused into thinking he had the capacity to resolve other conflicts.

It is now nearly a decade since he departed No 10. Time enough to lend a cooler perspective to one of the longest-serving occupants of that address? Time for a balanced and rounded assessment of Blair that includes the warts, but also has the all? If that is what you are looking for, you will not find it here.

• Broken Vows: Tony Blair – The Tragedy of Power is published by Faber (£20). Click here to order it for £16