Because we are a deeply sexist society that has that sexism baked into the nation’s core values. Women don’t get paid less because they choose to, unlike what Carly Fiorina claims. They get paid less because, as Amanda Marcotte states:
That said, the notion that women are making “personal choices” to make less money and therefore it can’t be sexism is pure poppycock. Women’s choices aren’t made in a vacuum, but informed by societal and familial expectations and attitudes that steer women away from being full competitors in the workplace and towards prioritizing domestic duties so that men don’t have to deal with them.
If you’re told from the cradle that girls aren’t as smart or good at math as boys and your efforts to join math and science programs result in a wall of sexual harassment, giving up and deciding to pursue a career, like teaching, that is less threatening to the sexist order is going to feel like a more attractive option. It’s particularly silly to deny that it’s sexism at play when women but not men scale back their ambitions in order to have children. The notion that it’s women’s job but not men’s to do the nitty-gritty daily work of raising children is the definition of sexism.
What’s interesting to me as a historian of the United States is the trajectory of different forms of discrimination. Racism remains as strong as ever, and in some ways stronger, but on the other hand, we have an African-American president of the United States who openly addresses racial questions. At the very least, racism is at the center of the national conversation, including by those defending it. Homophobia is declining at a rate unprecedented in the history of American bigotry. But sexism is just sort of stagnant. We don’t talk about it that much as a nation. It’s not a big part of the political conversation this year. Yes, Hillary Clinton is the favorite to win the Democratic nomination, but it’s not like that has led to larger national conversations about sexism. Sexism in pay rates remains basically the same. And while the historical movement for the Equal Rights Amendment always had its problems (primarily around ignoring the material concerns of women in favor of an esoteric and very middle-class goal), there’s no good reason the Democratic Party should not make the ERA a central plank of its platform. At the very least, there is a good moral argument to be made here that would be a concrete way to fight against sexism. But it’s just nowhere.