California Boycotting Arizona?

As you may have seen recently, Los Angeles city councilman Tony Cardenas wants the city of Los Angeles to stop doing official business with the state of Arizona over their recent stance on illegal immigration!

My question is... where is Congress on this? While I am hardly one to call for Congress to step in on anything, this is their job! The so-called Interstate Commerce Clause has been used to justify everything from the regulation and control of anything that crosses state lines in trade (such as guns) to the new Healthcare Reform Bill. Over the course of time and as a result of Supreme Court decisions, the use of the Interstate Commerce Clause has grown further and further from the original intention.

"[The Congress shall have power] To regulate Commerce with foreign Nations, and among the several States, and with the Indian tribes."

That middle part (the Interstate Commerce Clause) says that Congress has the specific and enumerated power to regulate commerce between the states. Regulation is not the same as control, but that is how it has been interpreted. Regulation means to keep something regular. One state, or even city, boycotting another is anything but regular. This, I feel, Congress does have the responsibility to keep regular.