'A Previous Instance'—Yamamoto and the Uses of Precedent

When questions have been raised about targeted killing—that is, about our practice of hunting down and killing terrorist suspects identified by name— defenders of the practice often bring up the case of the 1943 killing of Japanese Admiral Yamamoto, the architect of the attack on Pearl Harbor, and they cite it as a “precedent.” Now the first meaning given to the word “precedent” in the Oxford English Dictionary is “a previous instance taken as an example or rule by which to be guided in similar cases or circumstances; an example by which a comparable subsequent act may be justified.” Can this apply to the Yamamoto killing? In what way can a single instance like this from almost 80 years ago contribute anything to the permissibility of a highly controversial practice today? If the Yamamoto attack is a precedent, it is a non-judicial precedent and its invocation invites us to consider how precedent operates outside the framework of judicial decision. Beyond that, we must also ask what kind of justificatory work a single instance can do in normative argument? Does it justify by being a shining example of the rightfulness of actions of this sort? Or does it justify by beginning a line of analogical conduct that increases in its justifiability the longer it goes on?