The Bracero program, which was a guest worker program that allowed Mexican laborers to work in the United States on a temporary basis, did contribute to the problem of undocumented workers in the United States.
One reason is that the program was often exploitative, with workers being paid low wages and subjected to poor working conditions. This led some workers to overstay their visas or cross the border illegally in search of better opportunities.
Additionally, the program was often used by employers to suppress wages and working conditions for all workers, including American workers. This led to resentment among American workers and contributed to anti-immigrant sentiments, which in turn led to stricter immigration policies and greater efforts to crack down on undocumented workers.
Overall, while the Bracero program was not the sole cause of the undocumented worker problem in the United States, it did contribute to the problem by creating conditions that made it more likely for workers to overstay their visas or cross the border illegally.