Why do we need dialogue between ethical and legal perspectives on norms governing the initiation and conduct of interstate conflict? This essay will examine this question by first critiquing the 2013 Tallinn Manual on the International Law Applicable to Cyber Warfare, which sought to apply existing legal frameworks that govern international violence to a new form of conflict. While the manual is for the most part ethically commendable, the first half of the essay will highlight several of its ethical shortcomings and will then extract general reasons why international law nevertheless must be informed by ethical analysis. The second part of the essay will affirm the importance of law for ethical analyses of justified responses to the burgeoning phenomenon of sublethal harms. While states have always used sublethal harms to weaken adversaries, technological developments have magnified the regularity and effectiveness of these practices, particularly against free societies. Responses to such attacks may include—in addition to defensive countermeasures—punishments that deter and reform, and may target “indirect participants” such as financial supporters. However, determining which responses are ethically justified will require insights gleaned from criminal and tort law.