One question will define national politics in our time: Are Western Canadians prepared to sacrifice for the sake of the nation, now that Ontario is less able to help?
Population data from the 2011 census, released Tuesday morning, reveals a confident, growing Canada. One that is well-equipped to grapple with the demographic challenges facing all developed nations.
But while Western Canada leaps ahead, thanks to robust immigration and burgeoning resource revenues, the rest of the country lags. Quebec and Atlantic Canada are now fewer in number than British Columbia and the Prairie provinces.
And Ontario, home to almost four in 10 Canadians, has dropped below the national average in growth, another grim tiding for Canada's industrial heartland.
The Canadian social contract is under serious stress. Since the Great Depression, Ontario taxpayers have funded national programs that benefited poorer provinces. Ontario premiers from George Drew to Bill Davis knew that national unity depended on Ontario sharing its bounty. They grumbled sometimes, but they paid.
But as globalization eats away at the province's manufacturing base while rewarding the resource-based West, immigrants are starting to avoid the Great Lakes province. People and wealth are heading west.
Saskatchewan has more than made up for years of chronic population decline. Alberta is 11 per cent bigger than it was five years ago; British Columbia grew by 7 per cent.
Meanwhile, Statistics Canada reports "the rate of population growth in almost all census metropolitan areas located in Ontario slowed between 2006 and 2011."
The strains these population shifts will place on Canada are potentially enormous. Consider Quebec. Because the two provinces are adjacent and historically and economically intertwined, Ontario has willingly defended French Canadian interests on the national stage.
But Quebec's voice is weakening. In 1951, its share of the population was only four percentage points behind Ontario's (29 per cent versus 33 per cent). Today, the gap is 15 percentage points (24 per cent versus 38 per cent). The province is, as well, 7 percentage points behind the West.
How will the four Western premiers, currently represented by four different political parties, find the same ground that Queen's Park found with Quebec City? How will Alison Redford or Brad Wall explain to Alberta and Saskatchewan voters the need to share their province's oil wealth?
Finally, will Stephen Harper speak to the national interest? Or will he speak to those Canadians who supported him?
That base, by the way, is flourishing. The city of Toronto, a last bastion of the Liberal Party, grew by 4.5 per cent between 2006 and 2011, Brampton, on Greater Toronto's western edge, grew by 20.8 per cent. All of its ridings are Conservative, and will doubtless benefit from riding redistribution. And of course, the Conservative Party dominates from Manitoba to B.C.
The temptation, for the Conservatives, will be to concentrate on their own voters in suburban Ontario and across the West, ignoring the rest.
But while it makes economic sense to reward success and starve failure, national bonds could become dangerously frayed as Quebeckers contemplate an ever-diminishing profile and Atlantic Canadians continues to reverse its relative decline in influence.
The news isn't entirely grim east of Manitoba. The population of Newfoundland and Labrador grew by 1. 8 per cent over the past five years, reversing decades of decline. Almost eight times as many immigrants came to Prince Edward Island in the last five years as came in the five years before. Quebec City is one of the faster-growing communities in Canada. Toronto remains a magnet for immigrants.
Prime ministers and premiers have worked together in the past to smooth demographic shifts; there is no reason to believe the new generation isn't up to the challenge.
Census 2011 interactives: Explore the numbers