It's never gonna happen. Mexico won't even allow foreign investment in their oil industry. You expect them to suddenly give up their entire country? Their conspiracy nutjobs (they'd make our nutjobs sound sane) would be convinced the NAU was a plot to steal their oil.
Repeat after me, NEVER GONNA HAPPEN!
Mexico has two classes of people, the rich and the poor. The rich aren't slipping over our borders by the tens of thousands a day to come here. Their rejects and criminals have found a more furtile ground...us.
You don't think mexico not allowing investment in their oil industry wasn't discussed at Bush, harper, and fox's meeting in March?
Isn't mexico having an presidental election soon? I think with their next election, we'll see if they start allowing foreign investment. Looks like Calderon, just might be open for that.