Just Cyberwar

By Thomas Wester

Cybersecurity represents a major paradigm shift in global conflict and warfare. In his 1962 book, The Structure of Scientific Revolutions, Thomas Kuhn developed the notion that paradigm shifts in technology transform global dynamics.[i] Cyber-attacks are becoming more common; paired with increasing sophistication and greater lethality, cyber warfare will influence and dominate the war-fighting style of the 21st Century and beyond. In a 2012 article, President Obama warned that the “cyber threat to our nation is one of the most serious economic and national security challenges we face.”[ii] Mounting appropriate responses to this emerging threat will be crucial to ensuring our security as a nation. However, the response must be morally permissible and the currently accepted moral theories, including the Just War Theory, fail to fully address this emerging form of warfare. Furthermore, our nation’s responses will likely set the global precedent for responses to cyber-attacks. Thus, the morality of responses in cyber warfare is an issue that must be addressed.

The lack of clear direction with regard to potential responses to cyber-attacks raises many questions. How are we able to morally respond to an attack that may cripple our infrastructure yet not kill anyone, and how do we respond when a cyber-attack kills American citizens? Are we morally justified in having a kinetic response to non-kinetic aggression? By their nature, cyber-attacks do not have to destroy anything to be successful; nevertheless, these assaults represent a grave security threat. Yet, appropriately responding requires moral reasoning and justification.

The Just Warfare Theory states war is permissible “as a response to some egregious fault, such as a violation of human rights.”[iii] War should be proportionate, secure peace, protect the common good, and be avoided at all costs.[iv] However, formulating appropriate responses under the precepts of the Just War Theory is challenging because “cyber-attacks range from morally trivial to absolutely devastating,”[v] potentially having immense impacts on national security. Since many cyber-attacks may not directly violate human rights, response under the Just War Theory is often considered morally impermissible. However, we need to respond to these attacks in a manner which ensures our national security while still abiding by moral guidelines. Thus, there is a need for a broadening of the Just War Theory as it applies to cyber warfare; the conventional theory must be able to address unconventional warfare.

This broadening should include kinetic and non-kinetic responses to a cyber-attack. The theory should institute new precepts allowing for a reasonable response, necessitate a detailed analysis, and maintain the spirit of the original theory. Therefore, it needs to require that the attack is a direct act of aggression and will have lasting effects such as limiting defensive capabilities, destroying civilian infrastructure or violating human rights. Yet, responses must proportional, secure peace, and protect the common good.

Responses can be classified into two categories, kinetic and non-kinetic and are dictated by the nature and character of the attack. Kinetic responses should remain only allowable if the attack has intended lethal effects, causes human suffering or loss of life, or human rights are directly violated. Additionally, if a cyber-attack directly results in our susceptibility to a kinetic attack by eliminating defensive capability, and therefore we have reason to believe a kinetic attack is impending, we should be morally justified in taking kinetic military action in response to an attack that does not cause physical damage. Furthermore, as with many segments of critical infrastructure, if a cyber-attack has any order effects (2nd, 3rd, 4th, etc.) that result in human suffering, a kinetic response is justifiable. Yet, kinetic responses should be a last resort, cause a proportional amount of damage, and should attempt to be avoided at all costs while abiding by the just in bello guidelines of warfare.

Non-kinetic responses are justified if a cyber-attack directly targets our offensive systems or information, yet does not warrant a kinetic response. In the event of an attack on a system, we are justified in responding with a non-kinetic and defensively spirited counter-attack that invokes the minimum damage necessary to stop continuing cyber-attacks. However, the counter-attack cannot result in human suffering or elimination of enemy defensive capabilities. This broadening constitutes a self-defense of networks and information and allows us to protect the security of our nation and set an example for the rest of the world to follow.

Cyber will be an ongoing threat we will face as a nation now and for the foreseeable future.[vi] The threats we face from enemies are constantly evolving and cannot be addressed solely by current moral reasoning. This leaves us vulnerable to attack and limits our ability to respond to many of the grave threats we will face. Thus, it is necessary to expand the breadth of current moral reasoning. If we abide by the moral reasoning outlined in this paper, we will be able to limit the escalation of warfare and maintain the security and integrity of our nation. Without these limits, conflict will spread from the cyber domain and escalate having potentially devastating consequences; however, without the expansion of the Just War Theory, our ability to respond to many of the threats we face is thwarted, leaving us vulnerable and weakening our great nation.


Tom Wester is a Midshipman at the U.S. Naval Academy where he majors in Applied Mathematics. He conducts independent research in cybersecurity and security policy and was a delegate at the 2014 Naval Academy Foreign Affairs Conference Human Security in the Information Age.


[1] Hagerott, Mark. "What to Expect as Cyber Disrupts the Navy: Insights from Past Technological Revolutions at Annapolis and During Wartime." Lecture, United States Naval Academy, Annapolis, MD, November 8, 2013.

[2] Obama, Barack. "Taking the Cyberattack Threat Seriously." Wall Street Journal. Last modified July 19, 2012. http://online.wsj.com/article/SB10000872396390444330904577535492693044650.html.

[3] Eberle, Christopher J. "Just War and Cyberwar." Journal of Military Ethics 12 (2013): 54-67.

[4] Ibid.

[5] Ibid. 

[6] Obama, Barack. "Remarks by the President on Securing Our Nation's Cyber Infrastructure." The White House. Last modified May 29, 2009. Accessed August 18, 2014. http://www.whitehouse.gov.