Against nature? First of all, it is not against nature. It occurs in nature in numerous species. So in that respect it is natural.
Second of all, "against nature" does not equal that it is a lie. If it were "against nature" (whatever the hell that means) it would still have no bearing on this topic. Birth control is against nature. Shaving is against nature. Hair dye, makeup, and false eyelashes are against nature. And there is even some truth that hair dye, makeup, and false eyelashes are a lie.
But homosexuality is neither against nature nor a lie.
That homosexuality is against God's law is somewhat debateable, but not really relevant either. Since you cannot, according to the US Constitution, create laws based solely on religious beliefs, that particular argument has no bearing.