I don't concern myself too much with scaremongery and I am greatly relieved to see that Mike in Halifax does not either:

...Venezuela would not be holding back its US oil from the market, it would be selling it to China. Couldn't the oil that had otherwise been sold to China be then sold to the US market? Sure, there would be transition costs and jitters, and the price likely would jump up due to the uncertainty, but why would a changing of customers and suppliers mean great economic danger?

It is always funny when fearmongery is wrapped about the marketplace actions of an independent player. But what happens to Canada if - as if this would happen but play along - Alberta were to say "we make enough at 65 bucks a barrel...so let's sell to Canada for that and the rest of the world for what the market bears." If we use Canadian natural resources to create a global advantage or even foster a particular political relationship through sharing that advantage or even, like Venezuela, just aiming our supply in a particular direction - would that, too, be economic warfare?