The Confederacy? The interest seems to be the act of slavery and the war Lincoln is talking about must be the Civil War, which was taking place while Lincoln was addressing his second inaugural. Lincoln was reasoning that the Confederacy was fighting to keep slavery, which is the interest the "insurgents" have. Lincoln also did not want slavery to continue to spread, but he was fine with having slavery, "restrict the territorial enlargement if [slavery]".
Explanation:
as a one-branch federal government with three basic power as a three-branch federal government with one basic power
as one-branch state governments with three basic powers
as three-branch state governments with one basic power
Herman's Hermits were not one of the Mersey Beat Groups. Hope this helps!
