They've created this problem themselves by "winking" at it so long they are now swamped in illegals. The responsibility for enforcing laws of the land has always existed at the local level. Where the hell did they ever get the idea they had the option to "selectively" enforce laws of the land?? There should be retroactive prosecution of all law enforcement officials and politicians responsible for creating this problem including ex-presidents who have proclaimed group amnesties.
If, as appears clear, the federal government has so little interest in discouraging illegal immigration that it is as if the actual policy is to encourage illegal immigration as a cheap form of labor, why should anyone expect state/local governments to get too excited about what only some people see as a problem?