Something most people have overlooked about piping crude oil from Canadian tar sands is the stuff contains so many impurities there isn't a refinery in the US or Canada that can handle the stuff. So where will it go after it hits the gulf coast? The only refineries that are equipped for such low grade crude are in Venezuela. Venezuela, you may remember, isn't accepting any American shipping at the moment. So now what? We'll pipe it to Texas or Louisiana where it will sit at some storage facility until???????? Venezuela decides they like us again? Someone builds a refinery here? I don't see either one of those things happening in my lifetime. Nope, let the Canadians figure out what to do with the stuff, and more power to them.