LOL apparently they would sue on the grounds that they tried to screw Americans by outsourcing to “Mexican” trucking companies and got bent over the stump of the tree they cut down. LOL
Those US investors, as well as far fewer Mexican investors who invested north of the border, have had their investment stranded.
The Mexican govt won their case against the US pursuant to NAFTA Chapter 20 while the investors' claim will be pursuant to Chapter 11. Chapter 11 contains the investor protections against creeping or changing regulations.
Reagan insisted that the investor protections be included.