transracialism

The '60s produced the identity politics Obama decries, but they were also a time when transracialism became a driving force, especially among the young. This was the spark that gave the counterculture its funky fire.

Therefore, regardless of whether there is a physiological cause of or predisposition to the desire to change sex, I don't think such a cause or predisposition can consistently be required by the rejecter in order for transracialism to be legitimate.