If nations rank according to their wisdom and their virtue, what right has the American, a scourger and murderer of slaves, to compare himself with the least and lowest of the European nations? — much more with this great and humane country [England], where the greatest lord dare not lay a finger upon the meanest peasant? What is freedom, where all are not free? where the greatest of God's blessings is limited, with impious caprice, to the colour of the body? And these are the men who taunt the English with their corrupt Parliament, with their buying and selling votes. Let the world judge which is the most liable to censure — we who, in the midst of our rottenness, have torn off the manacles of slaves all over the world; — or they who, with their idle purity, and useless perfection, have remained mute and careless, while groans echoed and whips clanked round the very walls of their spotless Congress. We wish well to America — we rejoice in her prosperity — and are delighted to resist the absurd impertinence with which the character of her people is often treated in this country: but the existence of slavery in America is an atrocious crime, with which no measure can be kept — for which her situation affords no sort of apology — which makes liberty itself distrusted, and the boast of it disgusting.
And Abraham Lincoln in a letter to Joshua F. Speed, 24 August 1855:
As a nation we began by declaring that "all men are created equal." We now practically read it "all men are created equal, except the Negroes." When the Know-Nothings get control, it will read "all men are created equal, except Negroes and foreigners and Catholics." When it comes to this, I shall prefer emigrating to some country where they make no pretense of loving liberty — to Russia, for instance, where despotism can be taken pure, and without the base alloy of hypocrisy.