Why did William Moulton Marston believe a female superhero was needed?

William Moulton Marston believed a female superhero was necessary for two primary reasons: to improve the public image of comic books and to promote his vision of societal progress.

In the late 1930s and early 1940s, comic books faced significant backlash from critics who labeled them detrimental to children and a "national disgrace." Hired by publisher M.C. Gaines to counteract this negative press, Marston proposed creating a female superhero who possessed "all the strength of Superman plus all the allure of a good and beautiful woman".1

Beyond this strategic goal, Marston viewed the character as "psychological propaganda" for a new type of woman. Influenced by his long affiliation with the women’s suffrage movement and his personal relationships with pioneering women, he believed that women would eventually rise to lead the world into a new and peaceful age.21