Suppose I were to accept one of the common rallying cries of trans-antagonism: “Trans is a mental disorder.” I can completely sidestep the semantics of what should qualify as a “disorder” simply by replying “Sure. And then what?” There’s never any clear roadmap. “Therapy.” Well I went to therapy. That’s why I transitioned. >_>
It’s a simple and superficially appealing line of reasoning. It’s also completely wrong.
Those making this argument seek to apply the expertise of psychology and psychiatry – yet they wholly disregard the expert consensus of those fields on the treatment of gender dysphoria. The American Psychiatric Association, publisher of the DSM, stated in a 2012 report that “Overall, the evidence suggests that sex reassignment is associated with an improved sense of well-being in the majority of cases”, and “Gender transition can foster social adjustment, improve self-esteem, and relieve the anxiety and mood symptoms that can accompany gender dysphoria” (Byne et al., 2012). In a position statement, the APA concluded that transition is beneficial and medically necessary (Drescher, Haller, & APA Caucus of Lesbian, Gay and Bisexual Psychiatrists, 2012):
Zinnia Jones discusses more here.