Robin Morgan, a prolific feminist writer and radical activist who edited the landmark 1970 anthology “Sisterhood Is Powerful,” served as editor in chief of Ms. magazine for five years and helped organize one of the first protests of the Miss America pageant, died on Saturday in Manhattan. She was 85. The death, in a hospital, was confirmed by her son, the musician Blake Morgan, who is her sole survivor. From the front lines of a much-splintered feminist movement, Ms. Morgan gave voice to women as a poet, journalist, novelist, memoirist, agitator and iconoclast. She came of age in the civil...