Since its advent in 1841, the fair use doctrine has been hailed as a powerful check on the limited monopoly granted by copyright. Fair use, we are told, protects public access to the building blocks of creation and advances research and criticism. This Article challenges the conventional wisdom about fair use. Far from protecting the public domain, the fair use doctrine has played a central role in the triumph of a natural law vision of copyright that privileges the inherent property interests of authors in the fruits of their labor over the utilitarian goal of progress in the arts. Thus, the fair use doctrine has actually enabled the expansion of the copyright monopoly well beyond its original bounds and has undermined the goals of the copyright system as envisioned by the Framers. Specifically, the Article first analyzes the anti-monopolistic impetus for federal copyright protection and reflects on the original understanding of copyright as epitomized by a series of early cases on the rights of translation and abridgement. The Article then examines the impact of the fair use doctrine on the copyright monopoly and progress in the arts. All told, the Article calls for a serious reassessment of the role of fair use in the infringement calculus, especially in an age where networked computers and malleable digital content has enabled new forms of artistic and post-modern experimentation.