The country, its politics and the Liberal party itself have changed drastically since Pierre Trudeau mesmerized Canadians with the heady magic of Trudeaumania in the spring of 1968.
That world is hardly recognizable today.
The Canada of two generations ago was a country still revelling in the afterglow of the Centennial and Expo 67, wrestling with the tensions of the generation gap and ready to be led into a future of what seemed to be infinite possibilities.
People were pushing for a new kind of politics. They looked to replace the buttoned-down, backroom boys and their traditional mix of pressure and patronage with more grassroots involvement. It was a "power to the people" age.
The musical Hair celebrated The Age of Aquarius on Broadway. Stanley Kubrick's 2001: A Space Odyssey wowed audiences with its psychedelic special effects. Jane Fonda did the same with skimpy costumes in Barbarella. The Beatles were cresting with songs such as Hey Jude and Lady Madonna. The Rolling Stones were celebrating Jumpin' Jack Flash.
Stodgy was out and what now might be termed edgy was in. Into this volatile scene strode Trudeau, with his sandals and his ascot and his sports car and his beautiful (and ever-changing) women companions.
TV news was beginning to flex its muscles in politics and Trudeau seemed perfect for the cameras. The lenses softened the unconventional angles of his face and the hard, dark eyes. His pirouettes and backflips into pools were irresistible.
Cheering throngs often drowned him out when he campaigned that spring and as one contemporary account put it: "The crowds were seemingly interested in seeing or touching him."
Trudeau was described as "the greatest pop star this country has ever produced" in the book Mondo Canuck, a look at pop culture by authors Geoff Pevere and Greig Dymond.
He struck a particular moment and became what Christina McCall-Newman described in her book Grits as "a national symbol of arrogant virility and dazzling nonconformity."
The country was upbeat and looking for something new.
"At the time Trudeau came to prominence in English Canada as a cabinet minister in 1967, the country was in an uncharacteristically open and optimistic mood," McCall-Newman wrote.
Nelson Wiseman, a political science professor at the University of Toronto, agrees.
"There was this whole sort of more nationalist outlook ... rise of a nationalist feeling that didn't exist before," he said.
The post-war generation of immigrants was moving into a second or third generation.
"The country was multicultural then, it just wasn't as multiracial as it is today," Wiseman added. "The country wasn't the old British country it was."
There was a new flag with a bold red maple leaf. The pavilions of Expo had given the whole country a boost. In 1968, the medicare system, which would become a defining pillar of the country, went into effect on Canada Day, or Dominion Day as it was then known.
The separatist movement was still sorting itself out and the Parti Quebecois was just being formed. Rene Levesque would take the helm in October.
The federal government was trying to grapple with Quebec's aspirations, with its monumental royal commission on bilingualism and biculturalism, and taking the first tentative steps toward a bilingual public service. Trudeau, the erudite lawyer, writer and professor, had written a book on the question. Federalism and the French Canadians had become an unlikely bestseller.
Trudeau, with his visceral distaste for separatism, was seen as the man to bridge the gap between the country's infamous two solitudes.
And those solitudes lived in a much smaller country than today's Canada. The population was about 20.6 million. The federal budget was about $11 billion or about $70.52 billion in 2012 dollars. The deficit was about $800 million, roughly $5.2 billion today.
Today's budget is $276 billion, with a deficit forecast at $21.1 billion.
Social conservatism was starting to fight its last battles as the Sixties waned. Trudeau himself had loosened up the divorce and abortion laws and legalized homosexual acts between consenting adults. Ontario had controversially passed a bill legalizing horse racing on Sundays. Blue laws would slowly be whittled away over the next decade or so.
Human rights commissions were being established to fight the vestiges of racism.
Today many of those battles are fought and done. Gay marriage is in. Institutional racism is out, an object of public scorn as well as the laws. But the world economy is fragile. An aging population worries about getting kids through ever-more expensive universities and paying for old age. The idealism of the Sixties has faded into a sort of grumpy pragmatism.
Trudeau pere et fils both sought the Liberal leadership. But they were operating in different eras and different worlds.
"You can't compare them at all," said Wiseman. "Things are constantly changing. People want to make comparisons to the past, but things totally change.
"It was just a totally different time."
The younger Trudeau is 40, eight years younger than his father was when he ran for leader. He has been an MP for four years, but always on the opposition benches. His father was justice minister two years after being elected.
The son is a former high school teacher, with none of the public intellectual clout of his father. He's a married father of two. His dad was the country's most eligible bachelor when he ran.
Father and son might well have been looking to lead different parties.
In 1968, the Liberals were well on their way to becoming the natural governing party, attracting bright, young politicians across the country. In the election that June they would win a majority in the House of Commons, with 26 western seats, including four in Alberta.
Today, the Liberals have been out of power since 2006. They have been largely confined to urban eastern ridings for years, virtually extinct west of Thunder Bay. They crashed to the worst defeat in their history last year.
They have burned through four leaders in nine years.
The elder Trudeau, offered the helm of this wreck, might well have spun on his heel, hopped into his Mercedes convertible and vanished.
The younger, however seems set on the challenge.
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