you have that backwards. they can take it to court and get an injunction but they don't have the right to ignore anything unless the courts say so.Only Federal edicts and laws that are allowed to the fed are Constitutional. The States have the right to ignore Fed laws that are not powers granted to the fed by said Constitution.
if the federal laws are not constitutional the states can take that up in its proper place - the courts.
however, they do not have the right to 'ignore' anything.
Actually they do have the right to honor their laws until such time as a Court says otherwise.
again, that's just not the way the world works. no state can say that the enforcement of any federal law is illegal and it's lunacy to believe otherwise.You see the fed would have to take them to Court over it, the State has no compelling interest in starting a Court case, as they believe their law is legal and appropriate.