Jorge Castaneda, Mexico's former foreign secretary, recently spoke at a conference in San Antonio, and:

For the U.S., Mexico and Canada, a secure and prosperous future hinges on an increased level of integration that would create a type of "North American Economic Community," Mexican presidential hopeful Jorge Castaneda told reporters during a speech in San Antonio on Saturday.

"I think the best possible alternative (to the status quo in North American relations) is an intensifying of NAFTA in the direction of a European Economic Community..."

Castaneda's vision is that the three nations can strike a "grand bargain" by tackling each country's most vexing problems simultaneously...

Another approach would be to take the biggest current issues - such as homeland security and immigration - and try to solve them from a North American perspective, rather than one country's, he said.

So if the U.S. wants Mexico's cooperation to secure its borders from terrorists, and Mexico wants the U.S.' help to ease the flow of migrants north and south of the border, there is an incentive to work together, Castaneda argued...

I can imagine how Castaneda's lunchtime conversation went:

"If you give me half your steak, and I don't take the salt away, well, then it's a win-win!"

I kid, but this is quite a serious issue.
See also:
2002: "Mexico pushes for continental integration"
"Jorge Castaneda proves just how right Samuel Huntington is"
"Mexican Aggression And Its American Collaborators"
"The New Hemispheric Order"
The "New Partnership in North America": double-plus NAFTA
And, for a classic older quote from Jorge, see "Mexico to begin "propagating militant activities" in the U.S."

How much would it cost to extend the Gulf of Mexico to the Pacific?