No. We should annex Canada instead.
And Mexico.
I would rather wrought in hell then allow a North American Union. Borders are Borders that is that, and any such Union would qualify as Treasonable acts in violation of the Consitution and any politician who tries that crap should be executed.
"Wrought in hell?" Nice accident, that. You are aware of how new States are added to the Union, eh? If Saskatchewan up and said one day that they'd like to be annexed, following the proper channels, old borders (a rather abstract and meaningless construction) are no reason not to add another star to the flag. That's not what the other posters were implying, of course, but "Borders are Borders" is basically an appeal to tradition (aka an impediment to progress). Borders always have been a fluid thing, "wrought in hell" as they be sometimes.
I know you meant a North American Union, as akin to the European Union, and I also disagree with the idea besides perhaps more open trade agreements among the continent's nations. But execution for proposing such a thing as the NAU is not executing someone for treason, it's execution for an idea (one that wouldn't fly to begin with). Perhaps you're exaggerating for effect, but exaggerating nonetheless. Tends to make you look silly.