I’m repeating myself from another thread, but I might as well say it again. Marriage is a natural institution and has been since the dawn of civilization. It is a natural institution because man and woman are complementary to each other—biologically, anatomically, psychologically. Together they are capable of forming a marital union which has the potential of creating new life and creating new families, which have always been the underlying foundation of any society. Man and woman’s marital relationship makes possible the bearing of children, the formation of families, and the continuance of civilization.
It is because every society has recognized this fact as natural and obvious, and because they have valued the continued existence of their tribe or their nation or their civilization, that marriage has been endowed with state recognition.
And it is because of the lack of marital complementarity and lack of procreative potential that states have never recognized same sex relationships as marriage. They might have accepted same sex relations with equanimity, but they didn’t endow them with marital status, because they weren’t marital and conferred no benefit to the state.
No relationship other than between man and woman can ever be marital. A same sex relationship can never be marital, it can never be conjugal. It lacks the basic requirement of sexual complementarity.
The state can call it anything it wishes, but it is not marriage.