Nafta superhighway primer

If you haven't heard about the so-called "NAFTA superhighway," or if you have but want to know more without expending a lot of time, here's a good introduction from Rep. Ron Paul (R-Texas):

This superhighway would connect Mexico, the United States, and Canada, cutting a wide swath through the middle of Texas and up through Kansas City. Offshoots would connect the main artery to the west coast, Florida, and northeast. Proponents envision a ten-lane colossus the width of several football fields, with freight and rail lines, fiber-optic cable lines, and oil and natural gas pipelines running alongside.

This figures into a wider plan for a "Security and Prosperity Partnership" (SPP) agreed to last year by President Bush and the leaders of Canada and Mexico:

The ultimate goal is not simply a superhighway, but an integrated North American Union – complete with a currency, a cross-national bureaucracy, and virtually borderless travel within the Union. Like the European Union, a North American Union would represent another step toward the abolition of national sovereignty altogether.

There's one thing that makes me skeptical about the notion of such a nefarious plot:  If we're supposed to have "virtually borderless travel," why is the State Department going to make every U.S. resident who wants to visit Canada or Mexico get a passport just to return home — even a resident of Buffalo heading up to Toronto for the weekend?
I suppose one possible answer is that this is an intermediate step toward, literally, an "internal passport" — a national ID for a nation that stretches from Chiapas to Ellesmere Island.  It stretches the bounds of credulity for me…but I can't dismiss it altogether.