Those threats are real--best to follow another path. The right to secede is neither granted nor denied in the Constitution, however, there is a SCOTUS decision that impacts that right.
I am totally for secession. The warrens of the huge urban centers dictate, in a sense what the rest of America wants. They are the hubs of the money redistribution effort. They control the most electoral votes. Qualifications for voting and voter ID need to be implemented.