Alan,
I really don't think that is so. No matter how we try to make it sound there were many areas of the COnfederacy that did not support secesion and moved to the north and joined the Federal army. There were some areas that wanted to seceed from the Confederacy what was that one called, Winston or something like that,but were not allowed to. Kind of like what is good for the goose is good for the gander if you know what I mean. With the exception of South Carolina, every "Confederate" state supplied at least one regiment to the federal army and some provided many. The problem that the south had was when Bbeauregard attacked Ft. Sumpter (Federal Property) in stead of making the North draw back, it galvanized them into responding. In my opinion that was the straw that broke the camels back. Do you happen to know how many Confederate regiments were populated by men from the north? I don't have any info on that. Perhaps had there been more unity in the south they would have had more sucess. According to Rebel War Clerks Diary the authorities in Richmond were having a hard time keeping up with all the people who were applying for passports to travel to the United States (Of which they were part of). Wonder why they would do that.
Frank