I was going to write a post on nullification, but Steve Benen already wrote one so you should read his. It’s basically the political equivalent to a child screaming their throat raw because they didn’t get the present they wanted. It’s also just another example of a deeply selective view of the Constitution–Article VI states that acts of Congress are the “supreme Law of the Land.” But like the Commerce Clause, the General Welfare Clause, or the Necessary and Proper Clause, the Supremacy Clause ceases to exist if it comes into conflict with whatever conservatives feel like doing at the time.