The threat of "sexually insatiable female morons!"

Salon Reviews Harry Bruinius' "Better for All the World: The Secret History of Forced Sterilization and America's Quest for Racial Purity" (Note, you have to watch an ad to read it.)

The gist of the book is that more than 65,000 Americans were sterilized because of the risk that female morons (mental age 10-12) could pass for normal people, tended to have a lot of children, and would pass their mental disabilities on to these children. Moreover, large segments of the elite: Oliver Wendell Holmes, suffragist and first female candidate for president Victoria Woodhull, Alexander Graham Bell (who did later reject the ideas), and Theodore Roosevelt. The main original opponents were religious fundamentalists. The movement falls apart as it becomes apparent that it's rooted in weak science and that leading advocates were up for sterlizing 15 million people. Although while the subject is interesting, the book itself apparently isn't that good.