It is only when heroes depart that we miss them. The British thought they would be glad to see the back of Tony Blair. I miss him already. Mr. Blair’s last day in office began, appropriately, with questions to the prime minister. As befitted the best parliamentary performer of his generation, Mr. Blair modestly declared that he had “never pretended to be a great House of Commons man.” Yet it was he who crucially had persuaded that House to back his decision to go to war in 2003, defying two million demonstrators on the streets.

Yesterday there was little of the adversarial politics that usually makes the atmosphere so electric. However, while graciously acknowledging the congratulatory speeches, equally insincere on all sides, Mr. Blair managed to make the occasion memorable by a brief but spirited defense of his legacy in Iraq and Afghanistan.

He paid tribute to the latest British troops that have died, and told their comrades that he was “truly sorry about the dangers they face today.” But he reminded the British public that their sacrifice was not in vain, and that their killers, whether backed by Iran or by Al Qaeda, are our enemies. His moral courage is a quality his countrymen soon will miss.

Then it was off to Buckingham Palace to tender his resignation to the Queen. This was a private meeting, the last of many hundreds over the past decade. When Winston Churchill, the first of Elizabeth II’s prime ministers, resigned 52 years ago, he wore a frock coat and top hat.

In his time, Mr. Blair has abolished the last vestiges of Victorian tradition. The constitutional role of the monarchy, though, is not just a tradition. It means that no prime minister, however dominant, is above the law.

Mr. Blair may be the last prime minister to govern by the unwritten constitution that goes back at least 1,000 years. The European Union is already responsible for most of the legislation that governs Great Britain, and a new treaty marks another transfer of legislative, executive, and judicial powers to Brussels.

The flexibility that is the advantage of an unwritten constitution has, in practice, made it easier to erode the democratic rights of the British people. That is perhaps the worst of Mr. Blair’s legacies, but his recent predecessors are all guilty, more or less, too.

What of his successor? Gordon Brown is the first prime minister to have one eye and no heart. He lost his eye in a school sports accident, but he was born heartless.

The only thing the British have to fear is fear itself — personified by Mr. Brown. He has reversed the old principle “No taxation without representation” to read: “No representation without overtaxation.”

The new prime minister is what Scots call a “son of the manse.” His father, Reverend John Brown, was a “dominie” — a minister or teacher. The archetypal Scottish dominie was the great 16th-century reformer, John Knox, whose ferocious opposition to the idea of women ruling over men earned him the loathing of Elizabeth I.

Knox’s “First Blast of the Trumpet against the Monstrous Regiment of Women” rails against the danger that “the foolishe, madde and phrenetike shal governe the discrete, and give counsel to such as be sober of mind.”

Knox, of course, had women in mind. Remove the misogyny from this passage, however, and you might be listening to one of “Stalin” Brown’s diatribes against his enemies, Mr. Blair included. Discretion and sobriety — these are the highest virtues in Brown’s lexicon.

Brown would never echo his namesake Joe E. Brown’s immortal line in the film “Some Like It Hot,” “Nobody’s perfect!” Britain’s Brown is a perfectionist and something of a prohibitionist. No wonder he loves to vacation in New England — the pilgrim fathers would have been proud of him. Not that he is devout, though, his religion is politics.

At least the new prime minister won’t have to worry about the old one peering over his shoulder. Mr. Blair, despite last-minute objections from the Kremlin, is off to the Middle East to be the quartet’s new envoy.

This newspaper has voiced justifiable anxiety about this appointment. The last thing the Middle East needs is yet another meddlesome peace plan that will extract concessions from Israel and end by replenishing the arsenals of the terrorists.

But Mr. Blair gave a clue about his approach yesterday. He said that what the Palestinians needed, above all, is good governance. He has grasped one of the lessons of the Hamas coup in Gaza: that the Palestinians are not ready yet to run a state that can live in peace with its neighbors. He understands the impossibility of negotiating with Hamas, but he has no illusions about Fatah either. He is open to the idea that Egypt and Jordan might assume responsibility for Gaza and the West Bank.

The Middle East is a graveyard of reputations. But Mr. Blair has nothing more to lose. He stayed the course with President Bush. He did not think Israel’s retaliation against Hezbollah was “disproportionate” and he said so. Those decisions cost him his job. If any envoy can be trusted not to do more harm than good to the people of Israel, it is this one.