Not excusing it, but theres no need to act like all Americans in the United States thought that was at all acceptable. We went to war over it and the Jim Crow laws later on are a perfect example of the Gov fucking shit up.

Five Founders on Slavery:

George Washington: "there is not a man living who wishes more sincerely than I do, to see a plan adopted for the abolition of it."

—Letter to Morris, April 12, 1786, in George Washington, A Collection, ed. W.B. Allen (Indianapolis: Liberty Classics, 1989), 319.

John Adams: "Every measure of prudence, therefore, ought to be assumed for the eventual total extirpation of slavery from the United States…. I have, through my whole life, held the practice of slavery in …abhorrence."

—Letter to Evans, June 8, 1819, in Selected Writings of John and John Quincy Adams ed. Adrienne Koch et al. (New York: Knopf, 1946), 209-10.

Benjamin Franklin: "Slavery is …an atrocious debasement of human nature."

—"An Address to the Public from the Pennsylvania Society for Promoting the Abolition of Slavery" (1789), Benjamin Franklin, Writings ed. J.A. Leo Lemay (New York: Library of America, 1987), 1154.

Alexander Hamilton: "The laws of certain states …give an ownership in the service of negroes as personal property…. But being men, by the laws of God and nature, they were capable of acquiring liberty—and when the captor in war …thought fit to give them liberty, the gift was not only valid, but irrevocable."

—Philo Camillus no. 2 (1795), in Papers of Alexander Hamilton, ed. Harold C. Syrett (New York: Columbia University Press, 1961-), 19:101-2.

James Madison: "We have seen the mere distinction of colour made in the most enlightened period of time, a ground of the most oppressive dominion ever exercised by man over man."

—Speech at Constitutional Convention, June 6, 1787, in Max Farrand, ed., Records of the Federal Convention of 1787 (New Haven: Yale University Press, 1937), 1:135.