I have been watching reports of the preliminary injunction barring many parts of the Arizona anti illegal immigrant law. I think the judge ruled correctly. All parts of immigration enforcement has to be a federal responsibility, although the states can assist if asked.
The controversy reminded me of some of the experiences I had living in Burkina Faso and Senegal in the 1980's Both of their legal systems come from French law, through the prism of African culture. Police have the right to stop and ask you any questions. I remember the road blocks. I was always a little nervous. It's as if you had to prove that you had a right to be where you were. Now, we were never hassled and had just a few uncomfortable experiences, especially after the coups in Burkina.
In the US, on the other hand, we are free to do as we wish. The police can't stop you unless they have a suspicion you are doing something illegal. And even then, they have strict limits as to what they can ask. It would be a shame to lose that freedom, the feeling of liberty. If we all have to prove that we have a right to be here, instead of the police having to prove they have a reason to stop us, then we will have lost a great deal.