Why not? I would never support male circumcision if it were done my some random guy with a sharp rock, but most are performed in sterile conditions by professionals. So what's wrong with a girl getting the same professional treatment? When performed in similar conditions I think it is an easy comparison to make. I used to be heavily against it until I met people who have had it done and well aside from being forced into it as a small child, I don't have any valid reason to be against it.