Would the Repeal Amendment Actually Limit the Size and Scope of Government?

As I noted yesterday, libertarian legal scholar Randy Barnett's proposed Repeal Amendment to the U.S. Constitution—which would empower the states to overturn federal laws and regulations if the legislatures of two-thirds of the states agree—has been attracting support among Republican lawmakers. Barnett's co-blogger at the Volokh Conspiracy, George Mason law professor Ilya Somin, offers a qualified endorsement:

On balance, I think that the Repeal Amendment would be a small but genuine improvement over the status quo. Given my view that the present size of the federal government is far too large, I welcome efforts to cut it back. A very modest step in the right direction is still worth taking. If the Repeal Amendment could be enacted with little or no effort, I'm all for it. At the same time, I think supporters of limits on federal power should carefully consider whether this Amendment is the best possible investment of our limited political capital. Given the extreme difficulty of enacting any constitutional amendment and the relatively modest payoff to be expected from this one, it's possible that our resources might be better invested elsewhere. I'm not certain that's true. But the relevant opportunity costs need to be carefully weighed in advance.