Tyler Cowen proposes a solution to the immigration problem:
The Immigration Answer? It’s in Mexico’s Classrooms, by Tyler Cowen, Economic Scene, NY Times: Poorly functioning Mexican and Latino educational systems are a central problem behind current immigration dilemmas... If the United States took in a higher ratio of legal immigrants, and required more education, the entire North American region would be better off.
A high school diploma brings higher wages in Mexico, but in the United States the more educated migrants do not earn noticeably more... Education does not much raise the productivity of hard physical labor. The result is that the least educated Mexicans have the most reason to cross the border. In addition, many Mexicans, knowing they may someday go to the United States, see less reason to invest in education.
Mexican immigrants used to have higher-than-average levels of education, but today the average male Mexican migrant has lower-than-average education by Mexican standards. David McKenzie ... and Hillel Rapoport ... document this shift... (“Self-selection patterns in Mexico-U.S. migration: The role of migration networks” ). Less-educated migrants are more likely to bring crime and social problems, and they are less likely to assimilate.
In contrast to the men, female arrivals from Mexico still have above-average levels of education for their gender. A woman who migrates is most likely to have eight to nine years of education.
It appears that (relatively) educated Mexican women are more willing to break away from their families. Furthermore, Mexican women are less likely to work in agriculture or at hard labor, so education brings a higher wage in the United States. ... Nonetheless, illegal Mexican immigrants to the United States are usually male, if only because crossing the border is perilous and physically demanding.
This gender imbalance worsens the problems of immigration. Large numbers of young Mexican men have scant prospects for marriage ... in the United States. Men who marry tend to earn more money, behave more responsibly, commit less crime and assimilate more readily. Much of the so-called “immigration problem” stems from the illegality of immigration rather than from immigration itself. ...
A better immigration policy would tighten the border, while allowing in more legal immigrants from Mexico and other Latin countries, and require higher levels of education. Young Mexicans would see greater reason to invest in education, to the benefit of all Mexican society... The less educated Mexicans could be some of the biggest winners from immigration reform.
In the United States, employers have a greater incentive to train legal Mexican workers and combine their labors more effectively with capital investment... The legality and thus physical ease of immigration would also encourage the arrival of more Mexican women ,,, remedying the gender imbalance... In the short run, the greater number of immigrant children would raise costs in the United States for education and health care, but in the longer run those children would produce goods and services and pay taxes.
Taking in a higher proportion of women would relieve the migration-driven gender imbalance of rural Mexico. It is common for villages to have many unmarried young women, but virtually no young men. ...
Shutting the Mexican border is probably not possible, and it would paralyze American businesses and agriculture. ... The United States needs the courage to legalize a higher number of immigrant arrivals. The problems with current illegal migration are real. But most Americans benefit from Latino migration, even of the illegal kind, and they could benefit much more from legal and better-educated arrivals.
I don't always agree with Tyler, but having made a somewhat similar argument myself in Build It and They Will Stay Home, this time I do, at least with the idea that development within Mexico is the best long-run solution:
[I]n the long-run, the only real solution is to help poorer countries develop economically. ... If the wealth gap persists, we won't be able to build fences high enough, moats wide enough, or do anything else to stop people from trying to come here and from being successful in their attempts. We might reduce the flow, but no more than for, say, illegal drugs. Poverty prevents countries from doing all the things we think of as "fair," better environmental rules (but look back at the choices we made at similar stages of economic development before casting stones), health care, decent wages, etc. The very existence of poverty makes competition with wealthier countries look unfair to those affected by the entry of poor countries into the marketplace.
But how do we solve that? By isolating those countries from the world's wealth through protectionism, immigration restrictions, and other means so that the wealth gap persists while they try to develop on their own? Or are we better off engaging with poor countries economically and doing everything we can to help them develop and overcome the poverty that is holding them back while also helping the poorer residents of developed countries who might be affected by such policies?
People do not want to leave the place they grew up, leave their family and friends, and go illegally to a foreign country with a different language, a place where they are not generally welcome. It takes a powerful economic incentive to induce them to leave. I am not advocating opening our borders to anyone who wants to come here. But doing all we can to encourage investment in poor countries is the best way to solve the wealth gap and associated problems in the long-run, and that may mean accepting US companies outsourcing or moving to poorer countries during the transition period, and allowing more immigrants from those countries to come here and work. But by whatever means, economic development in poorer countries is the key to resolving many of the difficult problems we face and the only way to achieve a lasting solution.