My first reaction to the notion is, surely not. Sex is a chromosomal lock-in, not a personal decision (any more than you can decide to be another race).
God—or, if you prefer, Mother Nature—just doesn't get that one wrong. Both men and women can occupy spots up and down a spectrum of masculinity and femininity—and deformed genitalia is a real phenomenon. But when Genesis tells us that God made them, male and female, science backs it up.
Makeup, hormones and "gender reassignment surgery", the surely ghastly procedure that results in the removal of a perfectly healthy male penis and scrotum, don't actually transform a male into a female capable of that most central of female functions: the conception and birthing of children. Nor do they alter chromosomal structure. Similarly, a female cannot have a functioning penis scotch-taped to her midsection that's capable of impregnation.
The Diagnostic and Statistical Manual of Mental Disorders calls it "gender identity disorder", a persistent belief that one is the other gender. There is no laboratory test to confirm its existence. The manual (I'm going by edition four, edition five has been released) does not get into what the treatment should be. But it declines to call "gender identity disorder" a delusion, for reasons that are not persuasive to me: that is, they don't actually believe they're currently the preferred gender, just that they are—to use the phrase—a woman trapped in a man's body.
Is this a meaningful difference, really? I might announce that I'm George Washington. And then ask for the removal of all my teeth, to be replaced by wooden dentures. But psychologists and psychiatrists would, I presume, tell me that I'm not George Washington, and that if I continue to insist that I am, diagnose me as nuts. So what if I say, "OK, I'm Anonymous Attorney on the outside, but inside, I'm really George Washington." And then insist on the teeth removal, so that I can live a comfortable life as "who I really am". I just don't see a practical difference.
Homosexuals, whatever you may think of them, are not asserting the contrafactual: I am a woman, and I sexually desire other women. OK, got it.
There is even a bizarre phenomenon out there of people who seek the amputation of a completely healthy arm or leg: body integrity disorder.
Should the medical ethics surrounding that be any different than for "transgender"?
Ah, but "transgender" is no ordinary mental disorder. Because it touches on sex and sexuality, it comes wrapped up in thick layers of political correctness that insulate it from even being questioned. One who announces that they are "transgender" stands in the same shoes as a black, Hispanic, Jewish or gay person—armies of lawyers, rights advocates and D.C.-based groups stand ready to sue and smear anyone who dares raise an eyebrow.
And granted, it's not a widespread phenomenon, though taxpayers will be on the hook for Bradley/Chelsea Manning's "treatment."
My fear is that young people convinced of their "transgender" status are simply going to ruin their lives with medical and mental health affirmation that yes, you are in fact another gender, and we're going to help you get there. Instead of simply treating the root of the problem, which is the erroneous belief. People with this belief obviously have something bad going on mentally, for which they're seeking relief—they're depressed, or want some drastic change in their lives that they think will ease their discomfort. Slicing and dicing does not strike me as the healthy treatment.
A scan of the Internet does not reveal of raft of happy, well-adjusted and successful "transgender" people—I saw a stray university professor here and there (naturally). Most were freaks (literally), porn performers, or drug addicts.
As it turns out, there is some professional dissent. I found this November 2004 First Things essay Surgical Sex by Paul R. McHugh, former Psychiatrist-in-Chief at Johns Hopkins (1975-2001), who tellingly informs us that even after gender reassignment surgery, the "transgender" people are no happier. At some point, apparently, he supported stopping the practice of "sex reassignment surgery" at Johns Hopkins, to the relief of the surgeons who actually scrub up and do the cutting.
There's something about having the bloody mess in front of you that quickens your senses to the wrongness of something.