The first half of this movie, if sold as a finished product by itself, would be remembered alongside movies like The Jazz Singer. A technical landmark that mostly holds up but is held back by some cringe-inducing elements of the time. The reality is that Birth of a Nation keeps going after the assassination of Lincoln. And in the second half, the intent of the film becomes one with the text and the reality of what you're watching becomes impossible to ignore. D. W. Griffith has famously claimed that he had no ill intent in making the movie, but after having seen it, Griffith was either lying or so monumentally blind to his own prejudices that he should never have been allowed out of the house.
This movie is not anti-Union, it is not pro-Antebellum south. It is anti-Black. The movie frames the ending of slavery as the beginning of the end for civilized society in the south, brought about by a conspiracy of carpet-baggers and scheming mulattos and blacks. The answers to this issue are redemptive violence by the Klu Klux Klan and a return to the master-servant relationship of slavery. The movie frames "the loyal soul" blacks who accepted their ownership and didn't want slavery to end as the redeemable memebers, while those that welcomed the end of slavery did so entirely to then turn that systemic violence back against the whites.
I genuinely do not believe that you can understand how malicious and hateful this movie is if you haven't seen it. One can have it described to them, one can know the individual scenes of hatred within, but until one has experienced the slow, pernicious leaking of racial hatred firsthand, it can't sink in how contemptible this movie is.
Technically important? Yes, nobody is denying that. Even as the movie's message becomes more and more evil, it is shot with a competency and ambition that it would take the rest of the industry decades to catch up to. It is worthy of preservation in that regard. But it is also entirely indicitave of the era that a movie which makes such strides (and was the first film to see great success in America and be played in the white house) is a movie which frames the idea of a white man being expected to shake a black man's hand as an indignity which exceeds lynchings and enslavement.
