Introduction Modern Monetary Theory (MMT), a non-mainstream economic doctrine, has recently emerged from popular and academic obscurity to become a hot topic. Enthusiastically embraced by assorted progressive politicians, MMT allegedly demonstrates that such expansive government programs as the Green New Deal will not impose significant financial burdens on government. Economists critical of the theory range widely across the ideological spectrum, from George Selgin of the Cato Institute and Scott Sumner of the Mercatus Center all the way to New Keynesian Paul Krugman, and Post-Keynesian...