The conventional wisdom is that this country's privately owned critical infrastructure--banks, telecommunications networks, the power grid, and so on--is vulnerable to catastrophic cyber-attacks. The existing academic literature does not adequately grapple with this problem, however, because it conceives of cyber-security in unduly narrow terms: most scholars understand cyber-attacks as a problem of either the criminal law or the law of armed conflict. Cyber-security scholarship need not run in such established channels. This Article argues that, rather than thinking of private companies merely as potential victims of cyber-crimes or as possible targets in cyber-conflicts, we should think of them in administrative law terms. Many firms that operate critical infrastructure tend to underinvest in cyber-defense because of problems associated with negative externalities, positive externalities, free riding, and public goods-- the same sorts of challenges the modern administrative state faces in fields like environmental law, antitrust law, products liability law, and public health law. These disciplines do not just yield a richer analytical framework for thinking about cyber-security; they also expand the range of possible responses. Understanding the problem in regulatory terms allows us to adapt various regulatory solutions--such as monitoring and surveillance to detect malicious code, hardening vulnerable targets, and building resilient and recoverable systems--for the cyber-security context. In short, an entirely new conceptual approach to cyber-security is needed. [ABSTRACT FROM AUTHOR]