Women Directors

I'm studying film from 1960-present and am currently focusing on the 60's and 70's for a research paper.
Anyone who's studied cinema can name-drop the movie brats, the guys who all went to film school at around the same time and revamped the studios in America during the late 60's/early 70's: Coppola, Scorsese, Lucas, Spielberg...the list goes on.

What's notable is that it was a boy's club. The guys made movies about male fantasies, but there really wasn't a counterpoint of women directors who were able to make films about women's goals and aspirations. They existed in Europe, particularly in Germany, but why not in America?

This discrepancy continues today: just try and name 1 female filmmaker. Other than Coppola.

Am I right, or am I right? You probably can't name more than 3. Maybe.

What is it about America that makes women directors not as famous? Is it there a lack of female interest in the field, or do their films just fail? Is it a feminist issue?