re: #307 Expand Your Ground
Marriage isn’t something mentioned in the federal constitution; it’s an issue left generally to the states - and the states have gone in both directions (both to amend to give gay marriage rights, and to specifically declare that marriage is between a man and woman).
And DOMA is problematic because it attempts to override the Full Faith and Credit provision of the Constitution and the 10th Amendment - rights retained by the states to define marriage (among other things).