Guess what? People whose gender doesn't align with their sex have always fought for the US military. Just like homosexuals have always fought for the US military. They didn't just start enlisting during the Obama administration. You're just a bigot who wants to avoid having to answer the question "How does a gay or transgender person serving in the military negatively impact me?" The answer of course is it doesn't. You don't want your beliefs exposed as the immoral, empty beliefs they are.