Supporters of the U.N. Convention on the Rights of Persons with Disabilities are attempting to have it both ways. They dismiss as a myth any concerns about protecting sovereignty or parental rights because the treaty lacks a formal enforcement mechanism. They suggest that Congress can simply ignore any United Nations demand that isn't in our national interest.

Yet they simultaneously argue that U.S. ratification is necessary in order to force other countries to institute reforms. This inconsistent logic begs the question: If the treaty cannot be used to force changes in American law, how can it then be used to change the laws of other countries?

Ironically, no one highlighted this inconsistency more eloquently during Tuesday's floor debate than one of the treaty's most ardent supporters, Sen. John Kerry: "When have words or suggestions that have no power, that cannot be implemented, that have no access to the courts, that have no effect on the law of the United States, and cannot change the law of the United States, when has that ever threatened anybody in our country?"

Or any other country, for that matter.

Supporters argue the treaty gives us a seat at the international table. But America already sits at the head of that table. Our laws are the gold standard for protecting the rights of disabled persons. Nothing about Tuesday's vote changes that. We continue to be influential throughout the world in promoting the Americans with Disabilities Act as the model for other countries. Ratifying the treaty would not strengthen our hand, nor would it provide further rights or benefits for Americans at home.

At best, the treaty is ineffective. At worst, it could have grave consequences for U.S. domestic law. By their very nature, treaties diminish our sovereign authority to govern ourselves. Parties to this particular convention must answer to an unaccountable U.N. committee and are subject to its directions. If you believe Sen. Kerry, then the U.S. has nothing to worry about, but also no reason to support the treaty. If he is wrong, we have many reasons to oppose it.

Op-Ed originally published in USA Today.

You can add your voice to the debate about the merits of this treaty and others on my Sovereignty First page.