Read this and you will understand why things are the way they are:
http://www.cfr.org/publication/8173/north_american_community_approach_to_security.html
Bingo. The page you link to describes exactly what Bush and Fox are really discussing... essentially, a borderless North America, with no real border between Mexico and the US and Canada and the US.
If this happens, we will not make Mexico more crime free... we will become more criminal. We will not make Mexico more democratic, they will make us more Socialist.
If you mix dog squeeze with ice cream and eat it, it always tastes more like dog squeeze than ice cream.