This study aims to explain the Stuxnet-attack against Iran in 2009-2010 by using the IR-theory of structural realism. By doing so the theory also faces the challenge of the impact of the information revolution on security and international relations. The structural realism that is at hand is that of Kenneth Waltz and his Theory of International Politics from 1979.The study reaches the conclusion that Waltzs focus on the structure of the international system and the distribution of capabilities applies well to the case of Stuxnet as a cyber attack. The creators of the sophisticated Stuxnet, USA and Israel, also indicates that when it comes to this certain aspect of the information revolution and IR, states seem to still be the main actor. Finally the character of one of the major features of the Stuxnet-attack; the internet, is shown to have an anarchic structure that fits well as an extension of the realist view of the international system.