In fairness, I think you might do well to do some more research into Nathan Bedford Forrest's postwar history.
You might be surprised.
I commented earlier about this point, but let me try to restate:
There are many parts to every human being, including historical figures. Benedict Arnold was a genuinely great general. Ted Bundy was a charming, exceptionally intelligent man. Adolf Hitler loved dogs and was a fair architectural artist. John Wilkes Booth was one of the top actors of his day, celebrated and admired until April 1865.
You get the point, I hope. Whatever good the dark figures in history may have done in some parts of their lives, their hideous deeds forever mark them and their memory. Whatever good they may have done cannot outweigh the enormity of the bad.
If someone were to sign onto this or any forum using both the name and likeness of Hitler, Arnold, Booth, Stalin, Bundy, or any other such historical figure, that person would not be well thought of by most others on the forum. In my eyes, at least, Nathan Bedford Forrest is in that group of historical figures.
Countless times, people here on FR have skewered Sen. Robert Byrd because he was a member of the KKK? Yet here we have someone who apparently reveres the founder of the KKK, but presumably because he's on "our" side of the political divide, we're supposed to turn a blind eye to the screen name and NBF image posted over and over again.