http://www.theamericanconservative.com/dreher/mark-lilla-vs-identity-politics/

Identity politics on the left was at first about large classes of people – African Americans, women – seeking to redress major historical wrongs by mobilizing and then working through our political institutions to secure their rights. It was about enfranchisement, a practical political goal reached by persuading others of the rightness of your cause. But by the 1980s this approach had given way to a pseudo-politics of self-regard and increasingly narrow self-definition. The new identity politics is expressive rather than persuasive. Even the slogans changed, from We shall overcome – a call to action – to I’m here, I’m queer – a call to nothing in particular. Identitarians became self-righteous, hypersensitive, denunciatory, and obsessed with trivial issues that have made them a national laughing stock (drawing up long lists of gender pronouns, condemning spaghetti and meatballs as cultural appropriation,…). This was politically disastrous and just played into the hands of Fox News.