Ta-Nehisi Coates said this quote
“ The fear had precedent. Toward the end of the Civil War, having witnessed the effectiveness of the Union's 'colored troops,' a flailing Confederacy began considering an attempt to recruit blacks into its army. But in the nineteenth century, the idea of the soldier was heavily entwined with the notion of masculinity and citizenship. How could an army constituted to defend slavery, with all of its assumptions about black inferiority, turn around and declare that blacks were worthy of being invited into Confederate ranks? As it happened, they could not. 'The day you make a soldier of them is the beginning of the end of our revolution,' observed Georgia politician Howell Cobb. 'And if slaves seem good soldiers, then our whole theory of slavery is wrong.' There could be no win for white supremacy here. If blacks proved to be the cowards that 'the whole theory of slavery' painted them as, the battle would be lost. But much worse, should they fight effectively--and prove themselves capable of 'good Negro government'--then the larger war could never be won. ”