John E. Peters (jpeters@rand.org) is a senior researcher at the rand Corporation. The author thanks his colleagues Bruce Berkowitz, Edward Harshberger, Theodore Karazik, F. Stephen Larrabee, James Quinlivan, Gregory F. Treverton, and Benjamin Zycher for their comments on earlier versions of this paper and, at the Naval Postgraduate School, Thomas-Durell Young.