I haven't yet read Foner's book, so I don't know what he says, but I'm struck by two glaring omissions in your piece: Frederick Douglass and Ulysses S. Grant.

Frederick Douglass was purportedly the most photgraphed man in America in the 19th century and one who was very very widely heard and read. He was of pivotal importance to the story because it was he who legitimized the Constitution as a document of liberty and used that leverage against the very hegemony you rail against. Yes, old white guys built the government and they did it unfairly, but Douglass picked out the good and beat them savagely over the head with it (metaphorically speaking...), providing a template for MLK to do the same.

And, despite being in support of women's suffrage, Douglass refused to ally himself with their cause fearing it would muddy the waters and set both causes back.

The omission of Grant, while no less glaring, is undestandable since Grants character was the lesser assassination after the Civil War. But if you are going to cite Malcom X and Martin Luther King Jr. it's you should take care to note that what Malcolm and Martin were seeking to restore in the 1960's Grant had given and defended in the 1870's, with Douglass' full throated support. Douglass said that Lincoln had freed the slaves, but it was Grant who made him a citizen.