I would add that it is my understanding that much of tar sands oil and fracked oil that is what those pipelines were supposed to carry was for export. The US uses, I understand it, a "lighter" crude that is imported in large amount. So, if we put in this midwestern pipes it would be to sell, not to provide gas for our vehicles.

It is kind of like hatchery vs. wild fish; they are different. But, selling that crude would give the petrochemical companies more money.