by Thomas Rid (2013), Cyber War will not take place. (C. Hurst&Co, London), p. 165-166.
Talking about cyber war or cyber weapons, for instance, is didactically useful: the audience instantly has an idea of what cyber security could be about; it inspires creativity: perhaps evoking thoughts of "flying" or "maneuvering" in cyberspace (...). But too often analogies are used without understanding or communicating their point of failure. The line between using such comparisons as self-deception devices and testing devices (...) can be a subtle one.
A perfect illustration of this problem is the much-vaunted war in the ostensible fifth domain. (...) Indeed, referring to cyber conflicts as warfare in the fifth domain has become a standard expression in the debate. Five points will help clear the view. First: the war in the fifth domain has its origin as a US Air Force lobbying gimmick. The Air Force had already been in charge of air and space, so cyberspace came naturally. In December 2005 the US Air Force expanded its mission accordingly. (...) it should be clear where the expression comes from, and what the original intention was: claiming a larger piece of a defense budget that would start to shrink at some point in the future. Second: ultimately, code-triggered violence will express itself in the other domains. Violence in cyberspace is always indirect (...). By definition, violence that actually harms a human being cannot express itself in a fifth domain. Third, if warfare in the fifth domain (...) referred only to damaging, stealing, or deleting information stored in computer networks, rather than to affecting something that is not part of that domain in the first place, then the very notion of war would be diluted into a metaphor, as in the "war" on obesity. Fourth, cyberspace is not a separate domain of military activity. Instead the use of computer networks permeates all other domains of military conflict, land, sea air, and space. To an extent, that has always been the case for the other domains as well. But in the case of IT security an institutional division of labor is far more difficult to implement (...): the air force doesn't have tanks, the army has no frigates, but everybody has computer-run command-and-control networks. Finally, cyberspace is not even space. (...) the very idea of "flying, fighting, and winning.... in cyberspace", enshrined in the US Air Force's mission statement, is so ill-fitting that some serious observers can only find it faintly ridiculous - an organization that wields some of the world's most terrifying and precise weapons should know better. The debate on national security and defence would be well served if debating war was cut back to the time-tested four domains.