SCOTUS has disagreed numerous times, not on a moral basis ever.<quoted text>
Both the 5th and 14th amendments require equal treatment for all persons under the law. The Golden Rule is not just a promise of the founding documents, it is required by the constitution. As procreation is not a legal requirement, no one has presented a legitimate governmental interest sufficient for denial of the fundamental right of marriage.
"In the courtís final analysis, the governmentís only basis for supporting DOMA comes down to an apparent belief that the moral views of the majority may properly be enacted as the law of the land in regard to state-sanctioned same-sex marriage in disregard of the personal status and living conditions of a significant segment of our pluralistic society. Such a view is not consistent with the evidence or the law as embodied in the Fifth Amendment with respect to the thoughts expressed in this decision. The court has no doubt about its conclusion: DOMA deprives them of the equal protection of the law to which they are entitled."
The differences between marriage with/without kids and gay couples;
A apple tree bearing fruit.
A apple tree not bearing fruit for some reason.
A walnut tree who never bears any fruit wanting to be a apple tree.
A walnut tree hanging apples on it's branches pretending to be a apple tree.
The claim that if the government doesn't 'require' apple trees to bear fruit, then it is discrimination not to call walnut trees apple trees too is simply silly.
Marriage is a cross cultural constraint on evolutionary mating behavior.
Gay couples do not just fail in the primary essence of marriage, out of all relationships, they are the oxymoron of marriage.
Moreover, if you remove the element of procreation, you dumb down marriage to just a friendship. Hardly a cause for government interest, let alone selective discrimination.