This question asinine.
The EEC, back in the day, really was about free trade--it started as an agreement about trading coal. The North American Union is about importing cheap labor. I mean, I could see a U.S.-Canada treaty as really being about trade. When you throw Mexico in, it is about labor. Petromex oil and tequila don't come close.
........ this next comment is a little off the topic of this post, but I don't feel like starting a new thread about it. I go to the Rose Parade most New Years, to the same spot on Colorado that my Grandfather first started going to back in the 30s. When the Marine Corps band went by, they got a respectible amount of claps, if you compare the volume to the various high school schleps that walk by with ranks curving like they got drunk the night before, got no sleep lining up with the floats at 6 am, and were always into music more than marching in the first place. The Marines go by in lock-step every year, and blare out the music in precision, despite the fact that the band is just an amalgamation of bands from various SoCal Marine Units.
But when a band goes by from Mexico, they get 10 times the cheers that the Marines do, despite the fact they aren't noticeably better than any of the various high schools bands that go by. Hell, they get about 5 times the chears that the USC band did.