Weeks after J.K. Rowling expressed disdain for a British employer firing an employee for stating sex is binary, another employer—this time in the U.S.—allegedly fired a freelance columnist for saying there are only two sexes. Jon Caldara, a regular columnist for The Denver Post, announced Jan. 17 in a Facebook post that the publication had fired him for his traditional, but apparently offensive and “insensitive,” beliefs about sex and gender. An editor’s note posted Jan.21 at The Denver Post confirmed Megan Schrader, editor of The Denver Post’s editorial pages, decided the publication no longer would run Caldara’s weekly freelance column,...