NAFTA is called free trade.
But this is in title only.
Sure NAFTA prevents tariffs on imports and exports.
But government subsidies of certain industries allows for an unfair market advantage and so virtual monopolies in things like agriculture.
When a large sector of the economy is put out of work the workers flood the cities looking for new jobs. This surplus labor makes workers expendable and in turn lowers wages and that causes more workers to look for better employment and so the result is mass migration, first into the cities and then into neighboring countries. Because legal immigration is difficult slow and costly and illegal immigration is instant and comes with benefits, many choose to migrate illegally. Some Illegals serve as exploited labor and some exploit US social benefits. Both things are true. Partisans seem to acknowledge only one side or the other based on ideology. But reality isn’t optional. The end result is high unemployment, lower wages, exploitation, and ethnic tension.
Solution, make legal immigration easier, get rid of social benefit for illegals, and end NAFTA.