I have some issues with this. Not the least of which is the absolute fact that the federal government has NO control over immigration, which is obvious to anyone who can count to 12 million.
But more to the point, state laws that prohibit, say, distribution of welfare to illegals do not interefere with anyone's control over immigration. Just because it AFFECTS illegal immigrants does not make it an immigration control issue.
If a state limits welfare to citizens, that in no way interferes with the government to control the actual immigration of those people. It only affects people the government FAILED to control. But the laws, themselves, do not interfere with any government attempt to control immigration.
Ergo, the (in)Justice Department really should keep their noses out of state affairs. Every state, like every individual, has not only a right but an obligation to defend itself. And if the government won't do their job, then the states are forced to.