Well, the USA considers oil as a, "Strategic Resource" (just like water). Here is a scenario for all to consider...
America says it doesn't want our oil, (that would be like the US saying it didn't want Canadian uranium for the "Manhattan Project"-ya, I know it's not the same but is a comparison of "strategic resources").
Canada would then, sell it to whoever is willing to pay and believe me, the Provincial and Federal government have have extensive environmental requirements and laws that the 'Big Oil companies"(US-owned) must follow & adhere to.
Who would Canada then sell to, on the world market...? What other nations of the world would like to crack open the vast resources of Canada...?
Europe is a consideration...they'd love to import crude from a politically/socially stable nation. And, from an economic point of view...costs in transportation and refining are the same.
There is one nation who just recently got its foot in the door, here in Canada......China.
Chinese oil companies have been trying to gain a foothold in the Canadian 'Oil-patch' for years and finally managed to get federal Canadian approvals in the last year. And the demand for the Chinese automobile market is growing every year. I remember as a kid, the oil-crisis of the 70's when OPEC shut off the oil supply....it shut America down. The myth that Tar-sand oil is expensive to extract is not, exactly accurate....Last I heard...oil prices must be at least $50 bucks (US) a barrel to be economically feasible. And China, NOW, has the money....
Imagine...The US and China, fighting over Canadian oil......

Babygirl's luv