Matthew Dowd offered these thoughts on Mexican immigration back in 2005. Frankly, not much has changed.
Dowd is proposing the idea that time will take care of the illegal immigration problem. Dowd correctly points out that birth rates have dropped in Mexico. Therefore, Mexico will have to create less jobs in the future. This is an interesting theory but only a theory.
Dowd turned out to be correct that birth rates dropped in Mexico. However, Mexico still has a problem keeping its people around. It's too tempting to walk north and make $ 6 an hour rather than $ 6 a day!
P.S. It's a complicated topic but this book makes a lot of sense: