Does the advent of cyber-war require us to abandon the traditional ethical framework for thinking about the morality of warfare - just war theory - and develop principles specific to the unique nature of cyber-attacks? Or can just war theory still provide an appropriate basis for thinking through the ethical issues raised by cyber-weapons? This article explores these questions via the issue of whether a cyber-attack can constitute a casus belli. The first half of the paper critically engages with recent attempts to provide a new theory of just information warfare (JIW) that is supposedly better suited to the unique character of cyber war insofar as it is grounded the broader meta-ethical framework of information ethics (IE). Yet the paper argues that not only is JIW fundamentally unsuitable as a way of thinking about cyber-war, but (in the second half) that it is possible to develop a different account of how we can understand a cyber-attack as constituting a casus belli in a way that is in keeping with traditional just war theory. In short, there is no need to reinvent just war theory for the digital age
