Back in the 70s and 80s the Confederate Flag just meant, at least to us Northern Kids, "the South" or "Rebel": Dukes of Hazzard, Skynyrd even Tom Petty all sported the flag in a harmless, non racial, sense.
I respect the viewpoint of people that still feel it means that.
Still, sometimes symbols get co-opted to the point where the general meaning has been corrupted and the "negative" connotation is too widely accepted for it to be worthwhile to keep arguing about the original, benign, meaning.
(See, for example, the Roman salute and the Swastika).
I've thought the Confederate flag might be at that point for a while now.
It's worth noting that prior to World War II, U.S. citizens used to pledge to the American flag in a similar "Roman" or "Seig Heil" position of the arm. To eliminate any similarity to the Nazi salute, the position was changed to the right hand over the heart.
