Paul Martin has just endured the shock of his political life, a shock more startling than his exit from the federal cabinet or losing the Liberal leadership 11 years ago.

Time, never Mr. Martin's ally, has become his enemy, just as Jean Chrétien planned when he announced this week that he wants to remain Prime Minister until February, 2004. At a stroke, and from a position of weakness, Mr. Chrétien suddenly turned the clock against his nemesis in a dazzling but ruthless display of political cunning.

No wonder Mr. Martin took three hours before managing to mumble a few platitudes afterward. Gone was his confidence, his game plan suddenly shredded. Having just turned 64, he knew that his time is now. In 18 months, he will be halfway into his 66th year - and asking Liberals to turn to someone old enough to receive a pension.

Paul Martin had prepared himself for a different arrangement with Mr. Chrétien, negotiated as always through intermediaries and from a position of unassailable strength. The Liberal Party wanted him as leader, and wanted him soon. That's what the polls said Canadians desired, the majority of the rank and file signalled, and a majority of Liberal MPs sought.

The deal he expected would have let Mr. Chrétien avoid a leadership review next February in exchange for departing in the spring, or fall at the very latest. There would no party bloodbath, no humiliation and no serious obstacle to realizing Mr. Martin's prime ministerial ambition. The aura of inevitability that served him so well would remain intact. For services rendered and political success anticipated, the party would turn gratefully to the heir apparent.

But now the spectre of sharing his father's political fate, something he believed he could avoid, must dance before Mr. Martin's eyes. He may yet avoid that fate - he possesses strengths his father never had - but there can be no denying that his age and now this long delay are obstacles in his path.

Of course, Paul Sr. never achieved that goal. He served the party brilliantly, one of its pillars both in government and opposition. He was the Liberals' Everyman, versed in domestic and foreign policy, schooled in the art of politics. He thought himself superbly, even uniquely, qualified to be leader, even after he lost the job to Lester Pearson.

But when his second chance arrived in 1968, time and more enticing candidates overtook him. He was 65 years old, yesterday's man in the eyes of Liberal delegates.

His son remembers every twist in the story, and in important ways, his story and that of his father run parallel: political animals, strong ministers, respected internationally, party stalwarts, defeated once for the leadership and almost the same age for a second attempt. Will the stories' outcome be the same?

Today's Liberal Party wants Paul Martin as its leader. The rank and file would have voted to deny Mr. Chrétien a leadership renewal next February. The painful certainty of that rejection produced his reluctant announcement this week.

But will Liberals still want Mr. Martin in 2004? A week, it is said, is a long time in politics; a year and a half is an eternity. Mr. Chrétien arranged his departure to provide as much time as possible for other contenders to emerge, for someone younger to deny Mr. Martin the leadership, so the fate of the father would, like some familial curse, be visited on the son.

Why, when facing certain defeat, did the Prime Minister not resign quickly? He was too proud - and he knew it would have produced a coronation for Mr. Martin, whose ambitions he so resented. That's why he dictated the terms of his departure rather than negotiating them as Martin supporters had expected.

So, Mr. Martin has been snookered, or at least placed in the most awkward of positions. Many Liberals who preferred him to Mr. Chrétien shuddered at the prospect of a bloodbath. They wanted a dignified succession, and now that they have been a chance to avoid regicide, Mr. Martin will have difficulty persuading them to forgo it.

At first, he could not believe that his party was being turned against him, but once the terrible reality took hold, he could not forgive the man responsible. A few of his loyalists portrayed the assault as a "coup d'état," but it more resembled a siege, the steady occupation of political territory until Mr. Chrétien was cut off from the rank and file in the hinterlands that previously had nourished him.

No philosophical cleavages separated the two; after all, for nine years they had been the most important men in government. Had severe and sustained policy differences marked their relationship, it would not have lasted. There were disagreements, of course, of the kind that always characterizes debates between strong-willed politicians. But their tension, and subsequent falling-out, had far less to do with philosophy than with Mr. Chrétien's determination to wield prime ministerial power and Mr. Martin's ambition to acquire it.

Canadians watching this unprecedented struggle - no sitting prime minister with a majority in Parliament has ever been unseated - might fairly wonder what the fuss was about. If the struggle did not involve matters of high principle, and if both men were in their mid-to-late 60s, then would the outcome matter much to the country's future direction, let alone the daily lives of ordinary Canadians?

It mattered only to the extent that Canada is bereft of effective political opposition, so that the Liberals have become the de facto governing party. Whatever political change occurs, even if marginal, will take place within its ranks. Indeed, this fratricide probably never would have occurred had the Liberals felt threatened from without. But secure in power, they turned on themselves, and Canadians who desired moderate change - if only of personalities at the top - invested their hopes not in opposition politicians but in the internal opposition led by Mr. Martin.

He took on a certain diaphanous quality in which people could read into him almost whatever they wanted. Quebec nationalists viewed him as more in tune with their province's specificity. Western Canadians believed him more sympathetic to their region. Business, big and small, considered him their friend. Social activists hoped that inside the former finance minister beat the heart of a social-policy reformer. Environmentalists, remembering his interest in their cause as an opposition MP, thought him a potential ally.

Politically, the Liberals reckoned he would hold the party's Ontario bastion, and expand its strength in Quebec and the West, thereby guaranteeing not just continued Liberal rule, but an even larger majority than anything Mr. Chrétien had achieved.

He may yet realize his ambition. He remains the party favourite. His network of supporters spans the country, which he will be at liberty to roam free of ministerial constraints. He has never lacked money, nor will he. He can select events and interventions to suit his own purposes. He remains the heir apparent, and as long as that aura exists, he can expect at least some Liberals hitherto loyal to the Prime Minister will scuttle into his shadow to keep their own ambitions alive.

And yet, for all these advantages, some of Mr. Martin's allure risks fading away. He will be in the government, but without his previous influence on what it decides. He will receive no credit for its accomplishments, and dare not capitalize on its mistakes. But he will be asked continually for his opinions on its performance, forcing him to find the elusive fine line between offering support and hinting that he might have done things differently.

Memories of his services rendered as Canada's most impressive postwar finance minister will blur because, in leadership politics, it matters less (as Mr. Chrétien rudely discovered) what you have done yesterday than what you can deliver tomorrow.

Now John Manley, and not Paul Martin, is at the centre of the government. As Deputy Prime Minister and Minister of Finance, he has the chance to embellish his own leadership credentials through performance and substance. Eventually, he or someone else will emerge through the alchemy of leadership politics as the Anyone But Martin candidate.

His rival agents of change will appear both within the parliamentary party and perhaps among former premiers (Brian Tobin and Frank McKenna). As well, with the coming departure of Joe Clark and Alexa McDonough, the Progressive Conservative and New Democratic parties also will choose new leaders.

Like the Canadian Alliance leader, Stephen Harper, they will probably be half a generation younger than Mr. Martin. He will be a greybeard by comparison, an asset if Canadians are looking for a steady hand, but a liability if they want done with the old faces.

His father believed that service, ability and experience would make him Liberal leader, but generational change dashed his dreams. Now with another generational shift under way, Mr. Martin's nightmare is that his father's formula may fail yet again.

He also will face residual resentment among the Prime Minister's admirers that his personal ambitions almost wrecked the party and humiliated their doughty leader. Many will neither forget nor forgive what they view as perfidy unmasked, and will find someone around whom they can rally.

Chrétien loyalists will whisper what their boss believes: that beyond his unforgivable treachery, Mr. Martin lacks the temperament and judgment needed to lead. They will point to his skepticism about the Clarity Bill as evidence of his wobbly attitude toward Quebec. They will remind people of his formidable temper. They will minimize his role as finance minister, insisting that Mr. Chrétien approved the policy directions. They will dredge up stories, real or embellished, of plotting and skullduggery by Martin aides in the long siege against Mr. Chrétien.

And they will ask, sotto voce of course, why Liberals should decide that Mr. Chrétien is too long in the tooth and then turn to someone who isn't much younger?

That kind of animus never focused on Paul Martin Sr., but the father-son comparison also breaks down in another important, and perhaps decisive, respect. Mr. Martin's network of financial backers and rock-solid supporters, many of whom were with him in the 1991 leadership struggle, eclipses anything his father ever assembled.

Mr. Martin put together, quite literally, a machine within the Liberal Party with cogs in every province, and kept it humming for many years. His abiding task now, as the months drag on, is to keep that machine intact. If he succeeds, his chances of becoming leader will remain high.

The cruelty of politics, however, is that declarations of support are usually rooted in the expectation that a candidate will win. However, if the alchemy of time calls the inevitability of a Martin triumph into doubt, that doubt will corrode his support.

Mr. Martin must, therefore, maintain his position as the inevitable successor without benefit of a cabinet profile or influence on government policy and through the vicissitudes of time. If not, he will watch with dismay as the Liberal Party's instinct for power leads it in another direction.

It will not be easy, as it has been since Mr. Martin's departure from the cabinet, to maintain interest in what he has to say just because he, the inevitable successor, was saying it. During the interregnum, he has spoken often but said little, and of the issues he has even tentatively addressed, almost every one can now be overtaken by Mr. Chrétien's two-year "legacy" agenda.

Mr. Martin spoke of federal aid to cities, but Mr. Chrétien has promised unspecified aid for urban infrastructure. Mr. Martin told the Assembly of First Nations things it wanted to hear, but Mr. Chrétien has suggested he, too, will undertake new initiatives for aboriginal people. Mr. Martin, his reputation solidly established as a financial manager, wanted to stake out new ground on social policy, but the Prime Minister has already identified child poverty and health care as forthcoming priorities.

As the months pass, Mr. Martin's broad agenda for change may begin to look stale. Except in one area: what he calls the "democratic deficit."

There is a widespread, if unfocused, sense among Canadians that something is awry with their democratic system. Frustrated Liberal backbenchers give vent to frustrations about their role, but the frustrations extend to ordinary Canadians about th