First of all Joe illegal's employer pays Social security and medicare taxes on Joe illegal. Joe illegal will never see a dime of it when he retires in Mexico.
Also Obama and the democrats use the illegals for votes so they would like to make all the ones that are here legal and let more come in. What we need is a guest worker program which allows migrant workers to work in agriculture doing seasonal work that Americans wont do. By making it easier for these people to enter and exit the country legally they will be more likely to leave thier wives and children in Mexico instead of bringing them with them to live here. Many wont go home because it costs too much to cross the boarder.
If the democrats have their way, there should be enough Americans that will work for $12 an hour picking crops during the depression. Hunger is a great motivatator for people to want to work you know.