This article examines how and when States may employ countermeasures in response to malicious cyber operations that fail to qualify as armed attacks.11 The analysis applies equally to the use of cyber countermeasures against non-cyber activities.12 After discussing the nature of countermeasures, the article sets out the conditions precedent to taking them. It then dissects the requirements and restrictions imposed on countermeasures as they apply in the cyber context. The article concludes that countermeasures can prove an effective response option for States facing harmful cyber operations, but that due to various limitations on their use, they are no panacea. Highlighting their availability will nevertheless hopefully dampen the destabilizing incentive States have to characterize cyber operations as armed attacks, if only to afford themselves a legal basis upon which to ground effective responses.
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2353898
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2353898