The nullification movement would be laughable if those involved were not so deadly serious. At a time when the U.S. is facing economic crisis, foreign wars, domestic terrorism, infrastructure collapse and horrifying failure to prepare our children to compete in the 21st century, the extreme right-wing revives political theory that failed in the 18th and 19th centuries instead of addressing real problems of the here and now. The U.S. Constitution contains the Supremacy Clause (Art. 4, No. 2) for a reason: The Founders of our nation had just lived through a decade of government under the Articles of Confederation, which gave power to states to ignore most federal laws. That didn't work, so the Founders made federal law supreme.
Forty years after the United States adopted our Constitution, South Carolina passed a bill "nullifying" federal tariffs it didn't like. The federal government sent warships to South Carolina to enforce the tariff, and that state temporarily backed down until we fought a bloody Civil War over the enforcement of federal law by an unpopular president (Lincoln) and the South's claims to "state's rights." Since then, we've seen periodic challenges to the Supremacy Clause, such as the attempt by Arkansas to nullify the Supreme Court's school desegregation ruling in Brown v. Board of Education. In response, President Eisenhower sent federal marshals to enforce federal law in Arkansas.
A panel of Arizona legislators "nullifying" federal laws that they don't like is clearly unconstitutional. I think they have more important things to do in Phoenix.