When might international computer hacking become an Act of War? Some within the hacker community have felt that international hacking wasn't being done right by the DoD - it could be done much more effectively and efficiently if left to the experts - civilian hackers. This position is interesting, but is it appropriate? What ARE the international implications of electronic network information operations which target foreign actors or states? How far can an operator go before his acts become an "act of war"? What type of retaliation by a target country is permitted under international law and custom? What are the rules? Whose rules apply? In a world where hacker groups are so bold as to declare war upon a nuclear-capable major world power, and countries take military action against non-state actors geographically located in a non-hostile state, these thorny issues attain paramount importance. This presentation explores these issues in an effort to help shed light upon this "dark secret" of international relations.