A strange radiation from space kills all male life on earth except for Superman and and Lex Luthor(who was in a bunker and inside his warsuit). Since Kryptontians are immune to the still lingering radiation Superman you know into a jug and gives it to the women of earth and leaves because the radiation still clings to him.
So leads to a generation of superboys, fast forward 13 years and Lex Luthor brainwashes them telling they shouldn't have to listen to no "Females".