Yep. The north avoided losing the war at Gettysburg but won the war by seizing the west.
I also enjoy the story of the Grierson raid where the Union cavalry rode out of camp north of Vicksburg and rode across Mississippi destroying supplies and tearing up railroad, riding back into the Union lines at Baton Rouge. It was made into a middling John Ford/Wayne movie, "The Horse Soldiers." One line from that movie always cracks me up. The lady who owns the plantation house that Wayne made his headquarters is serving the officers a fried chicken dinner, leans over the gentlemen showing a bit of cleavage and asks, "breast or thigh?" John Wayne and Bill Holden exchange knowing looks.