The whole point of economic freedom is to encourage commerce in goods and services.
While there may not be a bunch of top-hatted executives and politicians in smoky back rooms planning a new nation of the three, open borders are tantamount to an EU.
(1) Our border with Canada is now tighter than it has been in generations.
(2) Our border with Mexico has been effectively unenforced for 20 years.
Allowing Mexican truckers into the US without having to abide by US rules and regulations is one step in that direction.
Except that isn't happening.
Amnesty is another.
That hasn't happened either. And we already had an amnesty, yet we are not governed by a council in Brussels.
Loosening of guest worker regulations is another.
EU residents aren't guest workers in any EU country they are in.
This isn't a conspiracy theory. It isn't even a theory. This is happening.
Except, of course, that it isn't.
The net effect is the same, borders which are merely a formality. In such a scenario, whether it is formalized or not, there is, in effect, a North American Union.