My Labor economics professor had a professor who went to capital hill some years ago to argue against raising the minimum wage. At the time all of the congressmen went out to lunch together. One of the congressmen was shocked that anyone could possibly oppose a minimum wage; his justification for creation of a minimum wage in the 1930s...
“It was the only thing we could do, and we had to do something, because all of the jobs were moving to the South.”
So at the time that minimum wage laws were enacted improvements in transportation were transforming the south from a primarily agrarian economy, and allowing manufacturing firms to benefit from the lower wages. The creation of a minimum wage was effectively a move by the manufacturing northern labor to out price their closest competition... Unskilled southern labor.
