Domestic production of petroleum products exceeds domestic consumption, and a majority of what is imported comes from our friendly neighbors to the north.

Even if we produced 200% of consumption, we would not be isolated from global market shocks, because the price of selling abroad (plus transportation) would be more attractive than selling domestically.

Imagine if your neighbor kept chickens, and sold you cheap eggs because he doesn't have to spend a lot of time or money delivering them (you're right next door). Then one day there's a guy on the other side of town willing to pay more for them, as many as he has. The neighbor has to buy a truck to deliver and gas it up and so on, but even without those costs your egg price will go up.