re: Target says Dudes can go in the Little Girls Room

The issue is so muddled and the debate so hot that precise numbers for Transgenderism are not currently known, or even possible. If we break out numbers for GID and Transexualism, however, we can see that they're tiny.

Treatment for GID in children and sex reassignment surgeries in adults indicates an approximate 0.1-0.2% of the population is affected. For Transvestitism, which is regrettably included under the Transgenderism label, the numbers can't be reasonably assessed because of the shame and guilt that prevents people, mostly heterosexual men, from adding themselves to statistics by seeking treatment.

Here are a couple of short but well-written articles that might give you an idea of the current state of Transgenderism in the U.S.:

Why We Don't Know the Size of the Transgender Population

Becoming Transexual: Getting the Facts on Sex Reassignment Surgery