Yes,Sanger was a racist eugenecist but her thinking at that time was right in the mainstream of American thought.
Nonetheless, expediency caused Sanger to distance herself from her radical past; for instance, she used soft phrases such as "family planning" instead of her original, more pointed argument that the poor were being manipulated into producing an endless supply of cheap labor. She also adopted the mainstream eugenics language of the day, partly as a tactic, since many eugenicists opposed birth control on the grounds that the educated would use it more. Though her own work was directed toward voluntary birth control and public health programs, her use of eugenics language probably helped justify sterilization abuse. Her misjudgments should cause us to wonder what parallel errors we are making now and to question any tactics that fail to embody the ends we hope to achieve.
*That is Gloria Steinem writing in Time mag in 1998.
How "mainstream" was she if she had to fake it for the, um, mainstream?