Org that infamously vowed to 'drive wedge between gays and blacks' equates marriage rulings with slavery

I've lost count of how many social conservative commentators, many of whom are clearly working off of some sort of coordinated intra-movement script (yes, they have those), have made the truly heinous logic leap of connecting the infamous Dred Scott decision with the US Supreme Court's potential ruling granting fifty-state marriage equality (see here and here and here). But somehow the National Organization For Marriage's attempt to connect the expansion of freedom for a minority population...