It's worth mentioning that until the Civil War the Federal government levied no direct taxes based on income or wealth on individual citizens. At that time the Internal Revenue Service made its first appearance. Income taxes were designed to pay interest in the bonds which financed the U.S. war indebtedness.
Glenn Beck is a child of the sixities. By that I mean that during the 1960s people began to talk about slavery as a great moral evil (with a capital 'E'). Before the Civil Rights era and Viet Nam, not many would say that. Someone familiar with Civil War literature from the late 19th century up until that time would be hard pressed to find authors who repeated the old abolitionist myths. Now everybody seems to believe it, Glenn Beck included.
It's also the reason that people who feel they must defend their Confederate ancestors insist that the war had "nothing to do with slavery." Personally, I feel no compulsion to defend Southern slaveholders any more than I should apologize for great men in described in the Bible who owned slaves. On a related point, no matter how you might feel about slavery in the United States, the way the institution came to an end was wrong (with a capital 'W').