Historically, however, there is no question that the country was founded by racists and white supremacists, and that much of the early wealth of this country was built on the backs of enslaved Africans, and much of the early expansion came at the expense of the massacre of the land's Indigenous people and broken treaties with them.
Eight of the first 10 presidents personally enslaved Africans. In 1856, the chief justice of the Supreme Court wrote on the Dred Scott case, in an infamous ruling that would be issued in 1857, that Black people "had for more than a century before been regarded as beings of an inferior order, and altogether unfit to associate with the white race, either in social or political relations; and so far inferior, that they had no rights which the white man was bound to respect."
America is not the same country it was, but neither is it the country it purports to be. On some level this is a tension between American idealism and American realism, between an aspiration and a current condition. America's systems -- like its criminal justice, education and medical systems -- have a pro-white/anti-Black bias, and an extraordinary portion of America denies or defends those biases.
As Mark ----- once put it: "The difference between the almost right word and the right word is really a large matter. 'Tis the difference between the lightning bug and the lightning."
Being imprecise or undecided with our language on this subject contributes to the murkiness - and to the myth that the question of whether America is racist is difficult to answer and therefore the subject of genuine debate among honest intellectuals.
Saying that America is racist is not a radical statement. If that requires a longer explanation or definition, so be it. The fact, in the end, is not altered.