sidhh, why you keep copmaring Canada to USA? you cannot compare them.. to start with, the population of USA is about 310 MLN. Population of canada is about 31 MLN.. so your questing about amount of airlines in the countries doean't seem to be legitimate. First european people came to USA almost 600 years ago and USA as a country is over 260 years old. First europeans came to canada less then 400 years ago, and Canada as a cuntry is existing for about 140 years.. Plus your question why most of population is concentrated along the USA boarder is not really smart. I think one has to understand that it has little to do with the southern neighbour. It's rather for the same reason why qatari population is concentrated in Doha only: because the rest of the land can barely be used for living...
if two countries are neighbours, it doesn't mean they suppose to have the same style... As the matter of fact, USA is developed much more than any other country, and much ahead than anybody esle in the world, maybe except of Japan only.. but Canada definitely has its own advantages comparing to USA...depends on what you want to compare...


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"What lies behind us and what lies before us are small compared to what lies within us."
Oliver Wendell Holmes