It was interesting awhile back --- I was watching a television show being broadcast in Ciudad Juarez -- a panel discussion where they were discussing the problems of massive migration --- the overburdened schools, the hospitals, the lack of infrastructure, the pollution, the huge crime wave --- because of so many people moving up into what had been a small border town that had it's own culture and ways. People moving up from all over Mexico and Honduras and Guatemala to find jobs in maquilas, too many people for the number of jobs --- their complaints were exactly like the complaints we have about massive migration. One of the panelists made the comment that massive migration of people IS instability, it is the result of instability and it leads to instability. Even the Mexicans complain about the destruction to their own culture when too many people move in who have different cultures and traditions --- and extreme poverty -- no ability to pay their own way.
Makes sense. I think that's what most Americans are concerned about too.