Because Margaret Sanger was only one of the American eugenicists who influenced the Nazis. The entire eugenicist movement did had a hell of lot more influence on the Nazis than Henry Ford did!
https://historynewsnetwork.org/article/1796
"During the '20s, Carnegie Institution eugenic scientists cultivated deep personal and professional relationships with Germany's fascist eugenicists. In Mein Kampf, published in 1924, Hitler quoted American eugenic ideology and openly displayed a thorough knowledge of American eugenics. "There is today one state," wrote Hitler, "in which at least weak beginnings toward a better conception [of immigration] are noticeable. Of course, it is not our model German Republic, but the United States."

Hitler proudly told his comrades just how closely he followed the progress of the American eugenics movement. "I have studied with great interest," he told a fellow Nazi, "the laws of several American states concerning prevention of reproduction by people whose progeny would, in all probability, be of no value or be injurious to the racial stock."

Hitler even wrote a fan letter to American eugenic leader Madison Grant calling his race-based eugenics book, The Passing of the Great Race his "bible."
You did not address this you ignored it.
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The state can never straighten the crooked timber of humanity.
I'm a conservative because I question authority.
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