Somehow, I've got this gut-level conviction that no solution will work which does not somehow create conditions which cause the Mexicans to not WANT to come up here.
If it were up to me, I would start from that premise, and then do *whatever* was necessary to create those conditions, beginning as humanely as possible, but stopping at nothing until the "problem" was solved.
Well I guarantee you that if a very heavy fines were laid on employers then this nonsense would come to a screeching halt! Walmart and the rest of them would have to start hiring American citizens and paying them a living wage! Instead of laying Mexico's problems on our front porch and expecting us to pay for the food stamps, medical care and education of their children while the Waltons fatten their billionaire bank accounts at our expense.