Spies, like soldiers, do a job and employ tactics that need justifying. I offer an argument for how Christian ethics may handle the moral problems of spying and do so by looking at the morally troubling tactics used by spies through the eyes of those who played an important role in shaping Christian theology and philosophy and have become normative in Christian moral thinking on the use of force. I argue that spying may be justifiable when we conceive the profession (...) as a kind of use of force that is governed by the just war criteria. Spying is a particular kind of use of force that takes its moral character from those who authorize it, with what justification, to what ends, and with what methods. Particular attention is given to the tactics of disregarding the rules of war, the telling and living of lies, running covert operations, and assassinating military and political leaders. (shrink)