I always thought that real bourbon can only be made in the great state of Tennesee, but this country song confuses me.
Bourbon has a stronger association with Kentucky than it does Tennesee. Many people even believe that bourbon has to be made in Kentucky in order to legally qualify as bourbon, which is a misconception. This association is for a good reason though, bourbon gets it's name from a county in Kentucky. After bourbon's creation, there is a long history of it being made elsewhere around the country, but after a bourbon market crash in the 1970's, the remaining distillers, with the exception of one, were all in Kentucky. That's no longer the case but, it created the impression that all bourbon comes from Kentucky. Tennessee has Tennessee whiskey, which is basically bourbon made in Tennessee. People often associate Tennessee whiskey with the 'sour mash' process, where some mash is taken from the last batch and used in the new batch. The association between sour mash and Tennessee whiskey is mostly because of labeling and advertising, most bourbons also use a sour mash. Easily the most famous whiskey from Tennessee, Jack Daniels, is labelled as Tennessee whiskey. This has created an even larger distinction, in the minds of the public, between bourbon and Tennessee whiskey. The difference between the two really boils down to regional pride.