The chapter sheds light on Hamas’s signal intelligence (SIGINT) and cyber warfare. It describes how, in the first decade of the 2000s, Hamas gained SIGINT capabilities that made it possible for Hamas to intercept the camera broadcasts of IDF UAVs, as well as the IDF’s visible tactical communication traffic. In the 2010s, Hamas began to invest in cyber warfare. This chapter also surveys Hamas’s successful use of various hacking methods to penetrate the smartphones of IDF soldiers and officers, extracting information and installing spyware and using social engineering techniques; descriptions of several real-life cases are included for illustration.

During an era marked by suspicion, and recurrent failures of ‘humint’ (human intelligence gathering), Cold War decision-makers were increasingly captivated and guided by the prognostications and intimations of ‘sigint’ (signals intelligence), ‘comint’ (communications intelligence) and ‘elint’ (electronic intelligence): that is, intelligence gathering through the interception and interpretation of electronic or electromagnetic signals and communications. Decision- and policy-making under the rubric of international law engaged continually with the would-be, could-be or might-have-been moves of key protagonists, as those moves appeared in electronic data. International legal order came to be marked, during the Cold War, by the latent or virtual agency of these overlapping ‘data shadows’ in ways that leave an enduring legacy today. This is demonstrated here by brief discussion of two instances of international conflict, and associated legal analysis, in ‘the “hottest” theatre’ of the Cold War: Asia.