"Why do people attack Tony Blair?" Peter Mandelson asked recently on BBC television in the course of an excellent three-part documentary on the Blair years. Mandelson was Blair's original consigliere and remained his most loyal apologist, even when Blair deserted him and allowed him to be ejected from the Cabinet twice.

It seemed a fair question, or at least an interesting one. After all, Blair is about to announce his imminent departure as prime minister after 10 years that have seen steady economic growth combined with low unemployment and inflation, not to mention the great orgy of self-congratulation after a power-sharing administration has just been set up in Northern Ireland (though not all of us are quite clear why we should be so elated to see power shared between a bigot and murderer).

There is perennial grumbling about public services and crime, and there is a deeply unpopular war. And yet even that hasn't really affected us so much: The casualties British forces have sustained over more than four years in Afghanistan and Iraq would have seemed a morning's work—or a few minutes'—during the great wars of the last century.

So, just why have people turned against Blair? Mandelson went on, "Is it because he's weak, is it because he's not a good politician, is it because he's a political failure, is it because he's without political skills?" Well maybe not, but that doesn't quite address the undoubted fact that Blair is leaving office more widely disliked and distrusted than most prime ministers for many years. No one doubts Blair's skills, but many people do think that he has indeed been a failure, above all in terms of what he once promised.

All through Blair's career, there has been a fascinating contrast, or dissonance, between appearance and reality, words and deeds, rhetoric and achievement. He captivated the British electorate 10 years ago, not least with his sheen of apparent sincerity and honesty. Although the religious faith worn on his sleeve would seem normal enough in an American politician, it's perplexing in a country where Church of England services are now attended by less than 2 percent of the population, but even that seemed at least authentic.

And so we believed him when he said that, after years of the grubby, sleazy Tories, his government would be "whiter than white." We didn't laugh, or not immediately, when he said early on, "I would never do anything to harm the country or anything improper. I never have. I think people who've dealt with me think I'm a pretty straight sort of guy." Those memorable words were spoken in the wake of an episode—the rules against tobacco sponsorship of sport were waived after a large donation had been made to Blair's party—for which most of us didn't think straight was quite the word.

Since then, there has been a long line of scandals with exotic names like Mittal and Hinduja, culminating in the baroque cash-for-peerages affair, and in the truly extraordinary moment last December when, for the first time in our history, a prime minister was questioned by the police at the official residence at 10 Downing Street. Straight sort of guy? He has been compared to Winston Churchill or to Margaret Thatcher, but the former prime minister he may best resemble is David Lloyd George, of whom historian Kenneth O. Morgan has written that, while Lloyd George's government had plenty of successes to its credit, what people disliked so much was "its tone as much as its policies, its atmosphere of intrigue and corruption." That fits the Blair years all too well.

There is a connection between Blair's religion, with his antinomian sense that "to the pure all things are pure," reinforcing a conviction that anything he does must therefore be virtuous, and his conduct in office, the spinning and smearing, the dirty tricks and the cynical maneuvers. Above all, his departure is burdened by Iraq and the burning sense of anger and betrayal so many feel at the way we were taken to war by Blair pitching a false prospectus and selling us a bill of goods, all in his most exalted manner and for what he believed were good reasons.

Trying to answer his own rhetorical question, Mandelson said, "The reason why people attack him is because he's strong, he's tough, he's skillful, he's a good politician and prime minister." But those would be reasons for admiring him, wouldn't they? What the British haven't forgotten is that this was the man who began his premiership by saying, "Ours is the first generation able to contemplate that we may live our entire lives without going to war or sending our children to war," and then took us into more wars than any prime minister in living memory, ending with an intractable and unforgivable disaster.

And that explains why in opinion polls so many of the British say—bafflingly on the face of it—that they are worse off, or worse served by the National Health Service, than they were 10 years ago. The statistical evidence shows that this cannot be so, but then polls are often used as displacement activity, with people saying they are angry about one thing and really meaning they are angry about another.

We remember the "dodgy dossier" and the other fraudulent claims made before the war—and Blair's subsequent refusal to apologize for them. We remember the horrible way the Blair junta "outed" as a source Dr. David Kelly, a distinguished government official, who then killed himself, and the way the junta nearly destroyed the BBC for reporting that the intelligence had been "sexed up" to justify the invasion.

Then we remember the "Downing Street memo," which later came to light, written in great secrecy for Blair's eyes in July 2002 and confirming that, with a decision for war already taken in Washington, "the intelligence and facts were being fixed around the policy." Not sexed-up, just fixed. Those words might be Blair's epitaph.

To be sure, he still has his defenders, but what's so telling is where you find them on the political spectrum. From an early stage, it was clear that he was a man of the right leading a party of the left, and it's not surprising that this has produced more than a few tensions and paradoxes. Even now, his most ardent admirers are way outside the Labor Party. "Brave, eloquent and in charge … a prime minister not just a party leader"—that was Charles Moore, former editor of the Conservative Daily Telegraph.

"Tony Blair will go down in history as one of the greatest premiers of the postwar period. His destruction of British socialism and his principled, tough and timely prosecution of the war against Islamic fundamentalist terrorism make him a giant"—that was right-wing historian Andrew Roberts, now a court favorite of George Bush and Dick Cheney. With friends like that ...

No wonder that those who once rallied to Blair now feel such bitter disappointment. The most poignant moment in that BBC series came near the end. Robert Harris is known to Americans as a best-selling novelist ( Fatherland, Pompeii, etc.), but he was originally a political journalist. He befriended Blair early and had closer access to him than any other during the 1997 election campaign.

And now? "I do think it's a tragedy," Harris said of his friend's career. "Blair was of my generation, and this was our shot, if you like." Then he added with studious understatement, "And I won't say that we messed it up but that it perhaps hasn't lived up to all the expectations of the rosy-fingered dawn of May the first, 1997." A tragedy for sure—but is Tony Blair its greatest victim?