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Before "National Security": The Espionage Act of 1917 and the Meaning of "National Defense"

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Larsen, Daniel Richard 


This article challenges the foundations of our understanding of the Espionage Act of 1917, which lies at the heart of the legal apparatus protecting government secrets. The fearsomeness of the Espionage Act arises from its enormous presumed scope, with it protecting all information “connected with the national defense.” This crucial phrase goes undefined in the legislation and is wrongly assumed to be synonymous with “national security”—a very different concept that was not invented until around the 1940s. This article explores the meaning of “national defense” within the Act. It connects the term to a specific historical concept that was widely understood in the early twentieth century. By reconstructing this long-forgotten concept, this article shows that both the text of the Espionage Act and its key 1941 Supreme Court precedent have been gravely misinterpreted. The Espionage Act is revealed to be dramatically narrower in scope than presently assumed, casting serious doubt on many of the recent and current prosecutions under the Act. The article also raises important, novel questions of due process concerning these prosecutions.



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Harvard National Security Journal

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