The British PM may be embattled, but his political legacy will be seen as very important, writes Richard Aldous
Eighteen months ago three of Britain's most powerful politicians held a clandestine dinner to discuss the end of the Blair premiership. One of those present was Tony Blair himself.
Exhausted by the crisis in Iraq, mired in vicious dispute with his own MPs about public service reform and suffering pangs of mortality about his irregular heart rhythm, Blair was on the verge of throwing in the towel.
Gordon Brown left that dinner believing he would be prime minister within the year. "When the tectonic plates appear to be moving," said the other guest, deputy prime minister John Prescott, "everyone positions themselves."
In fact, a rejuvenated Blair has outmanoeuvred them all. A historic third term beckons that will confirm him as Labour's most successful leader. More significantly, victory on May 5th will elevate Blair to the ranks of Britain's most commanding prime ministers.
In our age of unprecedented cynicism about politics, Tony Blair remains an extraordinarily popular figure. He may no longer be that "pretty straight kind of guy" with big ears and a nice smile whose approval ratings broke opinion poll records in 1997, yet he still wins over those middle Englanders whose votes turn elections. A recent poll asked which politician would be best company on a long journey: Blair won easily, beating even "Champagne Charlie" Kennedy, the Liberal Democrats leader.
The Blair factor has been central to a generation of Labour success.
The party had been in the wilderness for 18 bitter years before he led them to the landslides of 1997 and 2001. Blair gave Labour plausibility. He also gave them style. Some of his finest moments have come when he has spoken for the people at times of national or global crisis.
His simple, unaffected words on the morning of Princess Diana's death and his eloquence on September 11th, 2001, won praise around the world. When President Bush told the US Congress in the days after the Twin Towers attack that "America has no truer friend than Great Britain", it prompted a thunderous standing ovation.
Nothing tests the mettle of a leader more than war: Blair has won three of them - Kosovo, Afghanistan and Iraq. Doing so not only destroyed evil and corrupt regimes, it also established the Anglo-American relationship as the most powerful force for good in world affairs.
French president Jacques Chirac thinks that makes Blair a "bad European". In fact, the alliance which went to war in Iraq had support from the majority of the 25 nations which now make up the European Union. Indeed, aside from the war on terror, Blair's influence on the EU may turn out to be his most enduring legacy. The Blairite liberal Atlanticist agenda is winning the battle of ideas in Europe.
In France, both sides of the constitutional referendum debate recognise that les Anglo-Saxons (including Ireland) are in the ascendant; but neither camp, including the hapless Chirac, can work out how to resist them.
While the judgment of history so often rests on foreign policy, British voters have more immediate concerns. It's the economy, stupid.
Here Labour has delivered the kind of sustained growth and prosperity not experienced since the mid-Victorian boom. Added to this is progressive reform of public services and the biggest constitutional shake up since 1911. Hereditary peers were kicked out of the House of Lords; Scotland and Wales were granted devolved power; Northern Ireland, to which Blair has perhaps devoted more time and energy than any prime minister, got a framework for power-sharing government.
Stand Blair's record against that of Britain's most imposing prime ministers, and it is easy to see why history will judge him favourably.
HH Asquith advanced a similarly progressive liberal agenda, but was a disastrous war leader. Stanley Baldwin also understood when to stick and when to twist, but he was the architect of the appeasement that facilitated the rise of Hitler.
The 1945 Labour government has some claim to being the greatest reforming government of the modern era, yet its big beasts did not include the prime minister, Clement Attlee. It is hard to imagine any cabinet member saying similarly of Blair, as Ernest Bevin did during a leadership challenge against Attlee, "I'm sticking with little Clem".
Even Churchill cannot match Blair's electoral dominance. Perhaps only Lord Salisbury at the end of the 19th century and Margaret Thatcher at the end of the 20th have exhibited quite the command at home and abroad that Tony Blair now enjoys.
Lady Thatcher provides the key to how things might end for Blair. He is a great admirer of Thatcher. His New Labour project is Thatcherism for the left, but he knows she clung too long to power. When he became prime minister, he said he would not make the same mistake. This would suggest an elegantly choreographed exit from 10 Downing Street in May 2007, having marked 10 years in power.
Yet Blair shows every sign of feeling the hand of history on his shoulder. He certainly has a messianic side to his character. Although he has promised not to fight another election as leader, he insists that he will serve a full term.
"There's masses for me to do," he told Jeremy Paxman early in the campaign. Inevitably that would entail a fair share of crises, scandals and health scares - Harold Macmillan's "events, dear boy, events". The prize would be to leave office in 2009 as Britain's longest-serving prime minister.
In 1982 the young Tony Blair fought a byelection for the ultra-safe Tory seat of Beaconsfield. Almost a quarter of a century later he has come to exemplify the famous aphorism of Lord Beaconsfield - Benjamin Disraeli - that in politics success breeds success.
• Richard Aldous is a senior lecturer in history at UCD. His latest book, Macmillan, Eisenhower and the Cold War, will be published in June