A question about the opponents of gay marriage

[Foucaulf]

It's telling that the words "due process" have not been used once in this thread. Anyways:

Opponents of gay marriage need to claim empirically supportable harms of gay marriage.  They can't just say, God says no or I want to express my hatred through laws to punish people.

Isn't the whole point of the remnant opposition that gay marriage hurts their identity as constituted by religious principles, leading to observable, valid harm in society?