Natural law
Biology
Homosexuality
... are way more complex than that. I am not for federal legislation based on narrow, strict, religious interpretation of natural law. I am for leaving it up to the states - as I am for many things.
When the founders were around, every state had anti-sodomy laws. In fact, Thomas Jefferson changed the law in Virginia so the punishment for male sodomy was merely castration and banishment (IIRC) rather than the death penalty.
They were just fine with anti-sodomy laws.
So were most states until very recently; in fact, the only reason states can’t have anti-sodomy laws now is because of:
LIBERAL JUDICIAL ACTIVISM!
You call that small government? Ruling by a few people in black robes? I call that judicial tyranny.