Mega-Sized Canada (Alternate History)

[ThePoarter]

What would Canada look like if it had a much greater people. I'm talking either of the following amounts:

1. Two times as many people
2. Three Times
3. Five Times
4. Seven Times
5. Eight Times
6. Ten Times

In this case though the following stay the same though:

1. GDP Per Capita remains the Same
2. Near Future Technology
3. Population Distribution is the Same
4. Racial, ethnic and religious composition is the same
5. This develops natural over the course of 75 years from Post WW2 to now
6. This rate of growth is natural

Given this how would such a Canada effect the post WW2 world?

 

[Thousand Monkeys]

Most of Canada isn't all that habitable with all that rocky soil in the Canadian Shield. You're basically going to have megacities in the Great Lakes and Cascadia regions.

 

[ThePoarter]

Most of Canada isn't all that habitable with all that rocky soil in the Canadian Shield. You're basically going to have megacities in the Great Lakes and Cascadia regions.

Click to shrink...

Precisely. How would this effect geopolitics?