"So how hard would it have been for some state(s) to bring this case to the US Supreme court, and get a legal ruling on the matter?"
Since when did you have to go before a magistrate to invoke a God-given right? Lemme guess ....
Plaintiffs - "Oooh, oooh ... Yer Honor, can I use my God-given right to change my situation? "
Magistrate - "No, because the President doesn't like it."
Plaintiff - "Isn't the President trying to play God in this instance?"
Magistrate - "No son ... he is GOD."
The Supreme Court was in place to settle disputes between two or more States. When Roger B. Taney, Chief Justice of the Supreme Court wrote a dissent against Lincoln's suspension of the Writ of Habeas Corpus, Lincoln had a warrant issued for Taney's arrest. So how would the Supreme Court have been able to help? The Southern States reverted to their recognized God-given right to change their form of government. They didn't need to go and ask permission. They were asserting their Inalienable rights! Look up the word "inalienable" and tell me if it means one must ask permission first?