Sadly yes. I remember reading a book a few years back that laid out states that were wavering or on the side of the Confederacy only to be beaten down by the invasion forces. It laid out what may have happened if these states had left the union and it didn't paint a pretty picture for the north. If Maryland would have been able to leave I don't think the war would have lasted very long
And if Frogs had wings they wouldn't Bump their Butts.