Nine out of ten eugenicists in the 20th Century were also Progressives or Socialists, as central to the eugenic creed is the desire to engineer and centrally plan human reproduction and heredity. These were not people that believed in individual liberty. They certainly didn't believe the individual had the right to chose their own mate freely. They were statists, They were totalitarians at heart.

Socialists eat their children. The poets, artists, and radicals are murdered first once statists come into power. Statists abhor free thinking.