[QUOTE]Article 605: Other Export Measures
A Party may maintain or introduce a restriction otherwise
justified under the provisions of Articles XI:2(a) and XX(g), (i)
and (j) of the GATT with respect to the export of an energy or
basic petrochemical good to the territory of another Party, only
if:
(a) the restriction does not reduce the proportion of the
total export shipments of a specific energy or basic
petrochemical good made available to such other Party
relative to the total supply of that good of the Party
maintaining the restriction as compared to the
proportion prevailing in the most recent 36-month
period for which data are available prior to the
imposition of the measure, or in such other
representative period on which the Parties involved may
agree;
(b) the Party does not impose a higher price for exports of
an energy or basic petrochemical good to such other
Party than the price charged for such energy good when
consumed domestically, by means of any measure such as
licenses, fees, taxation and minimum price
requirements. The foregoing provision does not apply
to a higher price which may result from a measure taken
pursuant to subparagraph (a) that only restricts the
volume of exports; and
(c) the restriction does not require the disruption of
normal channels of supply to such other Party or normal
proportions among specific energy or basic
petrochemical goods supplied to the other Party such
as, for example, between crude oil and refined products
and among different categories of crude oil and of
refined products.
North American Free Trade Agreement 0.6 energy
It looks like a proportion is guaranteed, not necessarily an absolute amount. I think that Canada has adequate resources that domestic consumption would not be disrupted by demand from the south. After oil's production peak (or when demand exceeds supply, which is likely to be sooner), high energy prices will tend to reduce demand. I am sure you will find many sites full of anti-NAFTA and anti-Bush rhetoric if you only Googled for them.
I believe in free and fair trade, and GATT and NAFTA are a step in the right direction. Trade and economic interdependency reduce the chance of conflict. Parochial and xenophobic politicians (and lobbyists) tend to restrict trade and increase the chance of conflict.
Bush's visit to Canada seems to be an attempt to mend fences and reiterate sentiments of friendship, although he mentioned the missile defence program, suggesting he wants Canada on side with that. Paul Martin made a statement in reply, that Canada was a sovereign nation, and that any decision "for or agin" would be Canada's to make. I think he was speaking to Canadians rather than Americans when he said that.
Bush Presses Canada on Ballistic Missile Defense