Where did transgenderism come from?

Before the year 2000, no US state recognized same-sex marriage. By 2015, it was legal throughout the US and most of Western Europe. Before 2015 most Americans knew nothing about transgender issues. Within a year transgender issues are on the front pages of newspapers every day and schools may be forced to provide special bathrooms for trans students. The pace of change in the sexual revolution is not just rapid. It’s accelerating around the world. Why?

MercatorNet invited several scholars to answer this question, and today we begin publishing their answers.