Still labor in the south cost much more than elsewhere. What ever happened to Textile factories? South used to have the world largest clusters of textile factories, don't you know that? Not anymore
And yes, there was textile unions, they died about 20 years ago. Now, ask yourself, is there a textile factory survived here in USA? Afraid none as of this moment.
No, I know about there are few steel companies still survived in northern states but I blame on federal government for being too far with environmental regulation - EPA that caused steel, iron, coal, etc went down. EPA did good job to improve the air quality but killed a lot of jobs, so more damage, that why I just want EPA to be loosen up.
In southern states, they have right to work law and you are not forced to join the union, unlike in northern states that where you can be forced to join the union and pay their dues. It is supposed to make easier for business to set in the southern states and I haven't think about how bad is union in textile factories, so I thought it supposed to be less ruthless because they were less likely to strike over labor dispute and the owners have power to fire the employees whoever went on strike. The southern states favor managers more than employees, it has been for many years and the state governors did deployed the national guards to force union workers went back to job, in around 100 years ago.
Now, most companies rather goes to oversea like China because they don't want taxes and government regulation (labor, environmental, safety) so put unions as small reason, just slice of pie.
The government regulations are obviously mandatory, so is taxes, but it isn't mandatory for companies to form the union because it is up to workers, so in states with weak union environment, you as manager have power to reject any contracts that demand by union workers and let them goes strike, so you just hire permanent placement so throw union workers whoever went on strike out.
There are many Korean and Japanese assembly plants in southern states because they are too difficult to form the union so it is part of advantage for companies.