The solution to any large problem involves prioritizing a logical series of steps.
When you go downstairs and you find out the floor is all wet and realize you’ve had a water leak for some time. It wouldn’t make sense to start cleaning it all up until after you’ve repaired the leak, right?

The obvious answer is so easily missed so often. There are some politicians who talk about cleaning up the country by sending all illegal aliens back to their home countries, about stream lining the path to citizenship, about making all illegal immigrants felons, about the necessity to learn English, about denying them government services, about punishing employers who hire them, and creating a tamper proof non duplicatable identification card. All these things are worth consideration, but you have to repair the leak first.

Secure the border with fencing , armed guards, electronic surveillance, whatever it takes, then you can move on to the next logical step.

It seems completely practical to include a provision that would make it impossible for any one crossing the border illegally to ever become a citizen from this day forward.
This could be accomplished by taking DNA or finger print sample from any one crossing the border illegally and submitting this information to a central a data base. Then when someone applies for citizenship, INS would run their DNA or finger print through the central data base and if they had ever been caught entering the country illegally before, their application would be denied.

Making this information widely known, would immediately, significantly reduce the number of people willing to cross the border illegally.