Maybe it is futile to try to explain this to Justice Moore. Would he ever be able to understand that someone who is bisexual is capable of monogamy? Or that gender identity is not linked to sexual orientation? Or that incest is not the same thing as homosexuality? Trying to explain these concepts to Roy Moore is like explaining string theory to a clam.
It is easy to craft a slippery slope argument, for example; slavery must be maintained, because if we allow people to live in a completely free society, the family will fall apart, the institution of marriage will disintegrate, the government will collapse and Christianity will be rejected. Does this sound familiar?