Galton could not have envisioned that his social idealism would degenerate into a ruthless campaign to destroy all those deemed inadequate.
Yet Galton did envision it in "Hereditary Improvement", an article for Fraser's Magazine January 1885. In it, he envisaged a society of the rich (because gifted) living separately to the poor (because defective).
"I do not see why any insolence of caste should prevent the gifted class, when they had the power, from treating their compatriots with all kindness, so long as they maintained celibacy. But if these continued to procreate children, inferior in moral and physical qualities, it is easy to believe the time may come when such persons would be considered as enemies to the State, and to have forfeited all claims to kindness."
Becoming an enemy of the State is no picnic and it comes with the expectation that the State will act to destroy the threat.