...be very confused. It would be expensive for a piece of land that small to set up infrastructure, and who would they trade with? I can't imagine there would be many good feelings after a war of secession.
Of course, it just wouldn't happen. The U.S. military is way too strong, and one state (probably not even the entire population) against the U.S. military wouldn't be much more than a training exercise for them (which is a good thing).