What did "race" mean in the good ol' days?

Race never was exclusive to ethnic races, but referred to the fit and unfit of any race. Most sterilizations we done on Whites: Again, from Building a Better Race:

Popenoe and Gosney defended the German law through the 1930s. In both private correspondence and publications, Popenoe emphasized that the law was “not [a] hasty improvisation of the Nazi regime” but the product of years of sterilization practice and research. Indeed, Popenoe believed that Hitler's rise to power merely ensured that these ideas would be carried out. In an article published in the Journal of Heredity. Popenoe praised the German government for developing a solid eugenic policy that appeared to “accord with the best thoughts of eugenicists in all civilized countries.” In Popenoe's estimation, Hitler's ideas about human progress and the advancement of civilization were no different from those popularly expressed in the United States. Drawing from Hitler's Mein Kampf (1923), he quoted a passage remarkably similar to Hoover's Child's Bill of Rights. “He who is not sound and worthy in body and mind should not perpetuate his handicaps in the bodies of his children, ” declared Hitler in the volume.

By 1936, California eugenicists recognized that Hitler's persecution of the Jews might undermine the credibility and support of eugenics. Some continued to believe, however, that Hitler would be remembered not for his “political high crimes” (which would soon be forgotten) “but as the first head of a modern government who enforced legislation for the elimination of the unfit for the biological improvement of the race. Los Angeles Times columnist Fred Hogue quoted a “venerable student of history of international repute” as saying that “the evolutionary development of the race is much more important than passing political and social revolutions.”

But, by the end of the decade, Gosney and Popenoe wanted to avoid any associations with Hitler, who had little popularity in the United States. They avoided the racial categories used by Hitler and suggested that sterilization in America would be used selectively rather than on large groups. In 1940, Gosney warned his staff to avoid using racial terms in HBF literature. “We have little in this country to consider in racial integrity. Germany is pushing that. We should steer clear of it lest we be misunderstood. ” Popenoe wrote to a colleague in 1945, “When it comes to eugenics, the subject of 'race' sets off such tantrums in a lot of persons that one has to be very long-suffering!” Popenoe concluded that it was best to avoid the term altogether (though he and all eugenicists continued to use the term “race betterment” when referring to the goal of eugenics.

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Abnormality, rather than race, class, or ethnicity, differentiated those who, from a eugenic perspective, should not reproduce from those who should.

As a result, eugenicists used the term "selective sterilization" to explain the goal of eugenics: civilization would improve when only those considered “normal” were allowed to reproduce. Sterilization promised “sound minds in sound bodies” to fit the images promoted in Hoover's political speeches as well as the increasingly rigid and standardized images of beauty promoted by mass culture. Dismissing explicit racial categories, selective sterilization targeted abnormality—a flexible category of physical and mental traits that allowed for both hereditary and environmental causes of difference.

For example, in 1937, Frederick Osborn, president of the American Eugenics Society, stressed the importance of avoiding wholesale categorization of sterilization candidates. Desiring to distance American eugenics from German eugenics, he warned that it “would be unwise for eugenists to impute superiorities or inferiorities of a biological nature to social classes, to regional groups, or to races as a whole… Eugenics should therefore operate on the basis of individual selection.” He continued, “Fortunately, the selection desirable from the point of view of heredity appears to coincide with the selection desirable from the environmental point of view.” Thus, the term selective sterilization enabled eugenicists to target individuals based not on the cause of their supposed deficiency but on their desirability as a parent. Whether they emphasized selective or eugenic sterilization, heredity or environment, their goal remained consistent: to develop a mainstream following that believed in the concept of reproductive morality and accepted its mandate to sacrifice personal liberty in order to strengthen family and community.

[S]ciences and the resulting emphasis on environment, discoveries in genetics, and the Nazi use of sterilization—forced American eugenicists to justify sterilization on new grounds. Most important, eugenicists stressed that sterilization should be used to weed out those, usually women, who would not make capable parents. As the president of the American Association of Mental Deficiency argued in 1936, “Probably the most powerful argument for sterilization today is that which urges that no feebleminded person is fit to be a parent, whether or not his condition is hereditary and therefore likely to be genetically transmitted.”

Beginning in the 1930s, then, eugenicists who had previously established their careers on the principles of heredity seemingly contradicted themselves by inviting environmental factors to come into play, a move that previous historians have interpreted as an indication of eugenic defeat. But, ultimately, this was a smart tactic. It saved the movement from extinction, and it also widened eugenicists' sphere of influence and further popularized their goal to improve civilization by making reproduction a social and medical responsibility rather than an individual right.

As a result, sterilization gained supporters in the 1930s. Incorporating an environmental justification for sterilization paved the way for its increased use. Dr. Gladys Schwesinger, addressing the New Jersey Health and Sanitary Association in 1937, emphasized the “right of every child to have competent parents.” Playing on Roosevelt's New Deal policies, she argued that sterilization played a key role in “procuring a better deal for the child.” Children should not be entrusted to just anyone; the same supervisory control should be administered over parenthood as over teaching, nursing, and other services. Given that a child's personality could be “made or marred” at home, it was all the more important to protect children from “the wrong kind of parents.” Sterilization would spare “many unborn children the affliction of being born to unqualified parents.” Echoing the eugenic emphasis on reproductive morality as an essential component of modern society, Schwesinger pleaded for Americans to heed the call of social responsibility. “It is society's obligation, ” she argued, “to encourage the burden and responsibility of parenthood in the best and withhold it from the worst individuals of each generation.”