If I may clarify a couple things based on 8 years in and around Maquillas. Some easy to understand info
The major growth for Maquillas have been Pacific rim companies setting up shop in Mexico. The largest Japane Chamber of Commerce outside Japan is in Reynosa, Tamps. Mexico. For logistical reasons they are investing in Mexico, and hiring US management, instead of shipping products from outside NAFTA. Some of this is also because of import duties on non-NAFTA products.
Maquillas are only exempt from import tarrifs if the sub assembly or raw material originates in a NAFTA country. Tarrifs have actually increased on non NAFTA materials. In this area, NAFTA is working. It has brought economic development to North America.
It is misleading to compare maquilla wages. For example, most maquilla plants are required by law to have a Doctor on staff to treat the employees and their families. It is mandatory to offer free meals for every employee. It is required to offer free transportation to the workers. Employers pay death benefits. I can assure you that Maquilla wages are not .70 per hour, even before benefits. That is closer to the number that China is reporting.
Every Maquilla plant along the Texas-US border is unionized, I cannot speak with authority on the others. The unions negotiate contracts for their workers. Mexico has resisted, and has the maquillas, US unions from coming into Mexico. The UAW and others have tried to bring their unions but so far they have been unsuccessful. The Mexico unions work far closer than their US counterparts in plant operations. I have watched as the Mexico unions have worked side by side with management to compete. They understand they are in danger of losing jobs to China. Already we have seen companies that are very manual labor intense leave Mexico for China and some of the former Soviet block countries.
Just like in the US, if you have been fired from 3 jobs in 3 months, you will have a hard time finding another job. Maquilla managers meet regularly and are very organized. You are correct, poor employees have a hard time getting employment. Plus Mexico allows employers to share more information that dates employed. The US courts have stopped US employers from doing that.