Salt of the Earth was made by blacklisted Hollywood filmmakers in the early fifties who wanted to make the kind of movie that the studio system would never let them make. They found a miners' strike in New Mexico where a Taft-Hartley injunction prevented striking miners from picketing.  The women of the community took over the picket line and consciousness and relationships changed.  The movie is a triumph in many ways and works as a labor and a womens' movie (both rare).