Over at the Monkey Cage, Erik Voeten takes an interesting look at whether the U.S. failure to ratify the Convention on the Rights of Persons with Disabilities matters internationally:
Does a U.S. ratification actually help this process in other countries? I am not aware of any research that would give us much guidance on this but it is at least plausible. If domestic politicians start caring about disabilities rights not necessarily because they care about disabilities rights but also because they wish to be in conformance with international standards, then that push may be larger if the biggest (liberal) power in the world accepts this as an international norm. In my mind, then, the Senate missed an opportunity to plausibly make a small positive impact for a marginalized group across the globe at very little cost. This is not a strong statement but given that many foreign policy tools are so costly it is wasteful not to use the cheap ones.
I agree with this and this would be my argument for ratification. But I think Voeten isn't sensitive here to what the "sovereignty camp" sees as the costs. Even if one concedes (as I have) that its arguments about the direct impact of the treaty are unfounded, isn't there a broader cost in endorsing the practice of treaty-making regarding ever more specific aspects of national governance?
Those most concerned about sovereignty see the global governance project as a one-way ratchet that gradually but unmistakably limits the ability of societies to chart their own course. Given this worldview, even a relatively mild human rights treaty with weak enforcement provisions is an endorsement of the international community's right to manage domestic matters.