Many countries have or have had woman presidents! We had a woman president here in Panamá, and she was a disaster, but it had nothing to do with her sex and everything to do with her being an Arnofista, the Panamanian version of Crazy Right-wing Nutso Republicans.
So, will our Misogynist Friends (wait, they're not misogynists, they are simply following God's Word!) leave the U.S. if such a thing happens? We can only hope!