Just be aware that the US imports 40% of it's Oil from Canada if it stops doing so it will have a major impact on Canada's economy which is a thing no one wants especially considering the current issues with the Canadian economy. However it if wanted too it could stop importing oil all together today since it has more than enough local production, it would however increase the cost of gas and other petroproducts in the US since the US often imports considerably cheaper oil from OPEC and Canada while exporting fairly expensive US crude.