The majority of the 200+ year history of the U.S. military, women and men service members have not been treated as equals. It wasn't until the 1990's that women were allowed to serve in combat units after many years of fighting to be able to serve in the same roles as men. There has been a lot of progress made but there is still a large equity gap between genders. 

"My decision to register women confirms what is already obvious throughout our society-that women are now providing all types of skills in every profession. The military should be no exception." ~ Jimmy Carter

United States. President (1977-1981 : Carter), Jimmy Carter, United States office of the Federal Register   https://www.cnn.com/2015/02/13/world/carter-women-rights/index.html 

Rytman, Ashley. “Overcoming the Gender Gap in the U.S. Military .” Overcoming the Gender Gap in the U.S. Military, 10 Jan. 2020, https://site.nhd.org/31452169/home.