A sponsor of Alabama's immigration bill wrote an opinion piece in USA Today that emphasizes something I've repeated ad nauseam, namely that no such thing as sufficient enforcement exists.
Most people, including myself, wish the federal government would enforce its laws, but that is not going to happen any time soon. The people who oppose state initiatives are simply against any enforcement. They have little regard for the negative impact that illegal immigration has on the legal residents of the states or the rule of law.
Now, the numbers. From the Department of Homeland Security, here are the number of deportations for the past ten years.
Quite clearly, the Obama administration has deported far more people than any previous administration. Now, let's move on to getting rid of criminals. According to DHS, the U.S. deported 92,221 criminals in 2005 and 168,532 in 2010. And employers? In 2010 the administration started 2,746 formal workplace investigations in addition to audits, which was double that of 2008.
The Obama administration has enforced immigration laws more than any past administration, Republican or Democratic. You may think that to be positive or negative, but it is empirically true. It is therefore unfortunate that the myth of non-enforcement persists, and that this myth becomes an unsubstantiated rationale for congressional refusal to pursue anything beyond enforcement or for states to pursue harsh laws of questionable constitutionality.