The Supremacy Clause does state, that when a state law conflicts with a federal law, then... (keyword here legally speaking) GENERALLY federal law will supersede state law. But when a federal law conflicts with the constitution, it literally becomes null and void. All we as states are obligated to do, is stay within the frames of the constitution. As long as that is the case, federal law has not much ground to stand on trying to override state law. At least this is what I understood when I just read up on the matter.
The Supremacy Clause does state, that when a state law conflicts with a federal law, then... (keyword here legally speaking) GENERALLY federal law will supersede state law. But when a federal law conflicts with the constitution, it literally becomes null and void. All we as states are obligated to do, is stay within the frames of the constitution. As long as that is the case, federal law has not much ground to stand on trying to override state law. At least this is what I understood when I just read up on the matter.
That's because it assumes the federal law in question is... legal. Invalid federal laws don't supercede state laws.