There are four issues:
1) People living in this country who came here without permission, are staying here without our knowledge, and who do not pay taxes, but who do quite often consume community resources.
2) People living here illegally who are criminals.
3) People who want to come here illegally.
4) Government enforcement of our laws, and/or its abrogation and flouting of our laws.
We need to be clear with regard to issue 1, we can and should treat differing communities of illegals differently. They are not a monolithic group. They share a common culture, but they differ widely in their impact on different areas. In assessing how to treat people already here, it is quite possible to focus on differing areas differently. Personally, I think anyone living in a Sanctuary City should be an immediate focus. These cities are in blatant violation of Federal law, and they should be punished for it.
Migrant workers seem not to affect much at all.
And workers in differing industries will affect the local economies differently in differing States and cities. We think of this group of 11 million people or whatever as one group, but they are really many groups, with many different impacts locally.
It would be quite possible to develop a many year strategy to understand who is where, and decide perhaps to legalize some, and deport others, depending on a number of factors, including how long they have been here, their community involvement, etc. I personally would make their ability to speak English in that equation. If they have been here a long time, and have not learned English, they are not trying to blend in, and should be deported.
The issue of illegal criminals is easy: deport them all. Obama has been releasing them, to prevent their deportation, and there is no moral or legal justification for any of this. It is wrong, and it is illegal.
As far as the wall, it might again be useful to speak of “walls”. In certain areas, walls will need to be high and thick. In other areas, roving drones and ground sensors and ready ICE folks will suffice. We do not need a 2,000 mile wall. It may be sufficient to build a couple hundred miles worth of walls, in key place.
Most importantly, we must have the WILL–really, even the desire, or the integrity, or professionalism–to enforce our laws. Obama is not just not enforcing them, but is openly helping and supporting and encouraging illegal immigration. Hillary will do the same.
If Trump does nothing but do the job already assigned to him on the books, he will be marked success. But I think he will be ready and willing to take border control to the next logical level, to deport people who are victimizing both Americans and other illegals, to deport people who are negatively affecting American standards of living and comfort, to deport people we just don’t want for any reason at all, and to change the mentality of Mexicans to legal immigration, rather than the free for all we have right now, which punishes those who attempt to follow the law, and rewards, for now, those who impatiently break it.