In the novel I think slavery and the KKK and other social issues are deliberately painted from Scarlett’s self-absorbed “my problems take precedence” stance (one still held by many southern, and I’m sure non-southern as well, women and men). There are little windows in the book that let you know thinks were not as “happy darkies singing in the fields” before the war as Scarlett and Ashley pretend.
For example, when Scarlett returns to Tara during the war, all of the slaves who hadn’t been taken for the Confederate effort have run away, showing that they really weren’t happy being Mr. Gerald’s property. In one of the books best moments Mammy informs Miss Scarlett that she’s going with her to Atlanta (I believe it’s the “I saw it in the window and just had to have it” section) and Scarlett arrogantly tells her “you’re staying at Tara”. In a line not in the movie and that I’m paraphrasing because I’m not near a copy of the book, it says something to the effect of “Mammy looked at Scarlett and told her coldly 'Miz Scarlett… I am free. I will go where I like” and the line "Had Mammy said to Scarlett ‘I shall see thee at Philippi’ the words could not have been more chilling’.
Mammy loved her white children, but she was clearly glad not to still be a slave.
The KKK, while never the heroic organization of Birth of a Nation, really did start for different reasons than racism. It was essentially an underground citizen’s militia formed by thousands upon thousands of battle seasoned PTSD thoroughly defeated soldiers to guard against a military occupation of their homeland. It didn’t take it very long to become a society dedicated to bigotry, ignorance and racism (which, incidentally, is why it’s first president [though not, as sometimes referenced, its founder] Nathan Bedford Forrest, quit the organization [an odd moment of conscience from a former bigtime slave trader]). Ashley as portrayed in the book would certainly have joined for more romantic notions, while Frank would have joined for business reasons as well as unexamined social views. The attack on the shanty town was actually somewhat justifiable, however, due to the attempted robbery and rape of Scarlett. It wasn’t based solely in race: I could easily imagine urban black men today banding together to take revenge on an area where women could not go without being carjacked or sexually assaulted.
My dream cast for a remake:
SCARLETT- would have to be a worldwide talent search of course (but NO Julia Roberts, Nicole Kidman or other $20 million superstar)
RHETT- Johnny Depp
ASHLEY- Orlando Bloom
MELANIE- ? (Drew Barrymore? Very negotiable)
ELLEN- Catherine Keener
GERALD- Brendan Gleason
MAMMY- RUPAUL (oh alright, Loretta Devine, but only if Lady Chablis can be Prissy)
EMMY SLATTERY- Juliette Lewis
JONAS WILKERSON- Steve Buscemi
POLK- Lou Gossett, Jr.
BELLE WATLING- Jodie Foster
CHARLES HAMILTON- Haley Joel Osment
FRANK KENNEDY- Dennis Quaid
GRANDMA FONTAINE- Lily Tomlin
TARLETON TWINS- Mary Kate & Ashley Olsen- in drag