The whole idea that the Constitution is a living document is a myth. There is a process by which we can alter the Constitution, but it isn't by reinterpretation. The federal government is meant to be constrained in its powers in order to assure the liberties of the citizens.

> The whole idea that the Constitution is a living document is a myth

No, it's not; it's a fundamental inescapable truth of all documents, because meaning is dialogue between the author and the audience, change the audience and the meaning changes.

> Yup, the Constitution does not have a good mechanism for dealing with states racing-to-the-bottom, either in taxes or regulatory climate. This isn't really the kind of thing that you can regulate Federally, either, under the Constitution.

Sure you can; race-to-the-bottom among states only occurs because of the substantial nexus with real interstate and foreign commerce (not a distant potential impact), so even narrow views of the interstate commerce power would give Congress the authority to regulate to control it.