No offense taken, and I disagree! You say that: “Your stance on federalism has limits when it comes to moral issues, something Mr. Madison (and the 10th Amendment) stated were issues for the separate and sovereign states.”
I have not seen Madison state that moral issues were for the states and non-moral issues (whatever they be) for the Federal government. Point me to the statement by Madison if it exists and I will eat crow.
The issue of Federalism is in one sense resolved by the protection of marriage being in the form of a Constitutional Amenmdment. The representatives of the people vote through Congress (a national action in Madison’s analysis in Federalist 39) and the States ratify (a federal action in the same reasoning). I don’t think that Madison would be against an amendment at the Federal level blocking homosexual marriage (if he could bring himself to imagine the country he loved in such a circumstance). In fact I have evidence of this:
American citizens are instrumental in carrying on a traffic in enslaved Africans, equally in violation of the laws of humanity and in defiance of those of their own country. The same just and benevolent motives which produced interdiction in force against this criminal conduct will doubtless be felt by Congress in devising further means of suppressing the evil.
— James Madison, State of the Union,1810
Also: [I]f slavery, as a national evil, is to be abolished, and it be just that it be done at the national expense, the amount of the expense is not a paramount consideration.
— James Madison, Letter to Robert J. Evans
If the moral evil of slavery could be opposed at the national level by the Congress . . . with Madison’s approval . . . your argument that moral issues are solely for the states to decide is in tatters, if you primarily rely upon Madison’s idea of federalism to support it.
Mr. Madison wrote Federalist 45, which I quoted in my original post
The powers delegated by the proposed Constitution to the federal government, are few and defined. Those which are to remain in the State governments are numerous and indefinite. The former will be exercised principally on external objects, as war, peace, negotiation, and foreign commerce; with which last the power of taxation will, for the most part, be connected. The powers reserved to the several States will extend to all the objects which, in the ordinary course of affairs, concern the lives, liberties, and properties of the people, and the internal order, improvement, and prosperity of the State.--Federalist 45
I would assume moral issues fall under 'ordinary course of affairs'. Well they have for the past 200 years at least...