Some claim our immigration system is "broken," but the only thing that needs fixing is enforcement of existing laws. If these were correctly enforced and our borders were properly guarded we would not have millions of illegal immigrants here who have already broken our laws.
We don't want people who have disregarded our laws. We want the ones who will respect our system and Constitution. There are millions of those people in foreign countries waiting to come here legally and we should be encouraging them. Those people would help our economy the most and would assimilate into our culture, unlike the undocumented folks who now live in the shadows and fear deportation because they know they have violated our laws.
Of course, businesses love illegal immigrants because they will work for less and not complain.