[Aquinasfan]

He missed the third possibility, that marriage is an institution that was co-opted by the state as a form of taxation in about 1500 in England. It then lost it’s meaning between God and Man.

The State certainly has a compelling interest in the well-being of the family, since all future generations pass through the institution of the family, and the first principle of the State is the promotion of the common good. Therefore, it is the duty of the State to promote the welfare of marriage and families.

This is especially obvious in the case of adoption, which obviously must be regulated by the State.

Today marriage in some states like Florida is treated as one of the most voidable contracts there is.

Which is tragic.

[steve-b]

the first principle of the State is the promotion of the common good

As expounded upon in the political philosophy of "commonism".