Politics, not economics, sets the limit on Canadian immigration: Don Pittis
What are the economic limits of new arrivals from U.S.?

A well-known economic theory says that when it comes to people, you can get too much of a good thing.
As thousands of聽asylum seekers聽come across the Canadian border from Trump's America, there are many Canadian voices, including mainstream Conservatives, who believe we may聽have reached that point.
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A glance at internet comments and聽letters to the editor shows that some Canadians are reacting emotionally to media reports on the influx of new arrivals. But what about the economics?
Diminishing returns
In the economic principle sometimes called the law of diminishing returns, there is a text book example which describes an increasing number of workers coming to help dig in a聽garden of limited size.
One or two pairs of extra hands make the garden more productive, but as聽the number increases, the benefit falls, until, at extremes, there are so many people they are stomping on the plants and productivity collapses.

"The realistic part is we don't know. We absolutely do not have the magic number," says聽Bessma聽Momani, senior fellow at the Centre for International Governance Innovation (CIGI)聽in Waterloo, Ont.
While Canada continues to admit hundreds of thousands of聽new permanent residents every year, some as refugees and many more through the official points-based immigration system, the country also has a long history of being wary of new arrivals.
In the 1800s, Irish immigrants聽were seen as stealing jobs from earlier immigrants. As we've heard in recent聽debates over honouring political聽leaders of the past, Prime Minister Mackenzie聽King turned back Jewish refugees, many of whom died later in Nazi concentration camps.
According to modern refugee laws, that could not happen now, because Canada is committed to an agreement that requires countries to accept valid refugees who appear at their border.
Theoretically, if all the world's suffering people arrived on Canada's doorstep they would overwhelm the country's relatively small economy, and, like the workers stomping on plants,聽damage the economy.
Sinking lifeboat?
In the 1970s聽that was called the lifeboat theory, where rescuing too many people would cause the boat to sink.
But it hasn't happened yet. Refugees聽have to get to the border first, and as people seeking asylum from the United States may find, the qualifications for refugee status are quite strict.
Even if the number of refugees were to swell, the government could limit the number of people admitted under other categories to reach an optimum level, says Christina Clark-Kazak, professor of international affairs at the University of Ottawa.

There is a potential that admitting too many people, especially of one national group, could create a poor聽underclass as people get trapped in a cultural聽ghetto of generational underachievement. Clark-Kazak聽says that has happened in a few distinct聽communities, but it is an exception.
Evidence shows immigrants don't eat聽a piece of a limited pie. They make the pie bigger.聽
"The first generation may struggle, but what Statistics Canada has actually shown is that the children of immigrants do very well and that's across the immigrant categories," says Clark-Kazak.
"One would expect the children of highly skilled workers to do well, but actually the children of refugees also are more likely, for example, go to university than Canadian-born," she says.
Of course such a system would likely break down if, as in some Middle Eastern countries, the refugee population were聽bigger than that of the original host country, but studies around the world have shown that more moderate, but still high, levels of immigration are consistent with聽economic success. Others show immigration has no net effect.
Half a million a year
"There have been many many studies that show when it comes to Canada we could absorb, easily, 500,000聽immigrants a year," says CIGI's Bessma聽Momani, co-author of the book Diversity Dividend: Canada's Global Advantage. That half million economic capacity compares to the current intake of between 200,000 and聽300,000.
Canada's population is aging. Without immigration聽Statistics Canada says growth would聽stall.聽
But Momani says that besides adding absolute numbers, immigration聽stimulates an economy in innumerable ways.
It聽adds creativity in the workplace as people bring broader聽cultural perspectives.
Uh ohhhh...the <a href="https://twitter.com/hashtag/Racist?src=hash">#Racist</a> hand soap dispenser. <br><br>馃槻 <a href="https://t.co/lJEdVQgznO">pic.twitter.com/lJEdVQgznO</a>
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It helps businesses question assumptions and try new things, leading to innovation.
By exposing聽Canadians to global聽cultures, immigration makes international business seem more accessible. It offers access to those businesses聽through the language skills of immigrants.聽
Previous immigrant groups including the Vietnamese boat people and the Ismaili聽people pushed out of Uganda have been some of Canada's entrepreneurial stars.
Momani聽says that while there are clearly economic limits to the number of people Canada can absorb, all the聽benefits of immigration have repeatedly shown that we are well below those levels.
The issue, she says, is not economics. It is the kind of backlash we've seen in Europe and the United States where people reach a point where they decide that they聽are being culturally overwhelmed.
"The reality is, it's really about how much聽the political system can take," Momani聽says.
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