Slavery exists wherever Islam exists, and that includes the United States.
To rid the world of slavery, you must first rid the world of Islam.
The effects are apparent in many countries. Improvident habits, slovenly systems of agriculture, sluggish methods of commerce, and insecurity of property exist wherever the followers of the Prophet rule or live.
A degraded sensualism deprives this life of its grace and refinement; the next of its dignity and sanctity. The fact that in Mohammedan law every woman must belong to some man as his absolute property, either as a child, a wife, or a concubine, must delay the final extinction of slavery until the faith of Islam has ceased to be a great power among men.
Individual Moslems may show splendid qualities, but the influence of the religion paralyses the social development of those who follow it.
No stronger retrograde force exists in the world. Far from being moribund, Mohammedanism is a militant and proselytizing faith. It has already spread throughout Central Africa, raising fearless warriors at every step; and were it not that Christianity is sheltered in the strong arms of science, the science against which it had vainly struggled, the civilization of modern Europe might fall, as fell the civilization of ancient Rome.
-- Sir Winston Churchill (The River War, first edition, Vol. II, pages 248-50 [London: Longmans, Green & Co., 1899]).