Attribution - tracing those responsible for a cyber attack - is of primary importance when classifying it as a criminal act, an act of war, or an act of terrorism. Three assumptions dominate current thinking: attribution is a technical problem; it is unsolvable; and it is unique. Approaching attribution as a problem forces us to consider it either as solved or unsolved. Yet attribution is far more nuanced, and is best approached as a process in constant flux, driven by judicial and political pressures. In the criminal context, courts must assess the guilt of criminals, mainly based on...