Melville and racism

There's no doubt that Melville's Benito Cereno (1855) contains some reprehensible statements about race. The novel/tale sets as a basic assumption that the "negro"'is of an inferior race. Are these, however, Melville's views? He doesn't explicitly assign these statements about white supremacy to his protagonist, capt Delano - but the whole novel (aside from the transcript of testimony at the end) is from Delano's POV, so we can assume the white supremacy and racial stereotyping are of the character and of his time (setting is 1799' 50 years before the composition of the work). In fact we might say that at the 2nd level the novel itself refutes the racist presumptions of the protagonist. Because he presumes that the blacks are childlike and suited only for loyal servitude to their masters, Delano misinterprets everything he sees: he cannot comprehended what every reader will see well before he does that the blacks are in control of the ship, that capt cereno is being held captive. Delano's racist assumptions therefore almost become his own undoing. So is this a progressive novel?  Not really, because on the next level, the third level we might say, we have to a look at what Melville does not say: There is not the slightest bit of sympathy for or understanding of the plight of the blacks aboard the ship, who are to be sold in slavery to a Peruvian landholder. At the time of composition, just 5 or so years before the civil war, slavery and abolition were obviously huge topics in American public life , but Melville's does not even hint at this. His silence about the plight of the blacks and their bravery in taking control of the ship and of their lives - at the end we learn nothing of their fate only of the demise of the eponymous cereno - is a silence that speaks to us, or should. How can readers not see beyond the scope of this novel, beyond 1799 or 1855, and recognize that not only did Melville's protagonist miss the story but so did Melville?