Introduction

In his final foreign policy speech, President Bill Clinton listed among the United States’ top five military and security concerns the development of information warfare (Lacey). Given the importance of information technologies to the American economy and the U.S. military’s dependence on this system, any attacks on the information infrastructure could have severe consequences for the economy and for national security. For the U.S.’s best interests, taking the initiative in defining the limits of information warfare would be beneficial. The current U.S. trend toward concerning itself publicly more with computer network defense than computer network attack has prevented an adequate public dialog on the legalities involved with information warfare. The United States must address this issue before development of information warfare technologies goes much further. Resolving this issue at an international level can protect the United States from future information warfare attacks and present opportunities to retaliate against attackers.

Definition of Terms

Before exploring the implications of information warfare, a working definition of the term must be established. Due either to imprecision regarding information warfare’s specific operations or just that this form of warfare is very young, many definitions are available. The Air Force’s official definition of information warfare, articulated in the “Cornerstones of Information Warfare” report, is “any action to deny, exploit, corrupt or destroy the enemy's information and its functions; protecting ourselves against those actions; and exploiting our own military information functions” (Fogleman and Widnall). This definition, while widely used compared to most, seems rather broad. Almost every form of conflict, related to the military or not, could easily fit under this definition. Feasibly, an argument between lawyers could be defined as an “action to deny, exploit, corrupt, or destroy the enemy’s information and its functions.” While widely cited, this definition proves inadequate for the limits of this paper.

The discussion concerning information warfare in the past decade evolved largely due to the rapid development of technology in that timeframe. The widespread use of computers and networks greatly expands the opportunities for military exploitation of such systems. An effective definition, therefore, should include references to these technological advances. The National Defense University defines information warfare as “the use of information and information systems as weapons in a conflict where information and information systems are the targets.” While emphasizing the role of technology in such conflicts, this definition also places the agent engaging in conflicts as the military.

Even under this definition, information warfare may take multiple forms. National Defense University analyst and prolific writer Marting Libicki, while working under the initial definition of information warfare provided by the Air Force, identified seven distinct forms of information warfare:

1. command-and-control warfare: that which strikes against the enemy's head and neck

2. intelligence-based warfare: which consists of the design, protection, and denial of systems that seek sufficient knowledge to dominate the battlespace

3. electronic warfare: radio-, electronic or cryptographic techniques

4. psychological warfare: that in which information is used to change the minds of friends, neutrals, and foes

5. "hacker" warfare: that in which computer systems are attacked

6. economic-information warfare: blocking information or channeling it to pursue economic dominance

7. cyberwarfare: a combination of the previous six methods

While recognizing the diversity of information warfare methods available, this paper considers only the international legal implications of “hacker” warfare, more officially known as computer network attack. When the term information warfare is used in this paper, computer network attack is the implied method.

One final term must be understood before further exploring this topic. International law itself is a system of behaviors and customs governing relations between states. It is composed of two separate forms. Signed treaties among nations codify acceptable behaviors. Most treaties derive from previously existing customary law, which, while unwritten, greatly influences a state’s international relations and forms the majority of international law (Janis, 7). A significant difference between international law and domestic law is enforcement. In domestic law, the state, in theory at least, has the ultimate authority to regulate actions and behaviors within its territory. No body has corresponding powers on the international level. As Lawrence Greenberg puts it, “no police walk the international beat” (8). Each treaty signed includes enforcement criteria, generally a set of sanctions to punish the violators of that treaty. Since states ultimately decide whether they participate in a treaty, enforcement is basically voluntary. Sanctions apply only to member states. Even for member states, the effectiveness of sanctions from treaty violations is questionable. The sanctions must be sufficiently harsh to convince the country’s leadership to change its policies. For the most part, however, states regard international law as binding. Agreements concerning air travel, citizen’s rights in foreign countries, and international trade are just a few of the ways in which international law functions every day. The United States Supreme Court has previously considered international legal agreements signed by the United States and approved by the Senate as legally binding for the government. The United States’ compliance with international legal agreements to which it is a party and with international customs is thus required. The position of computer network attack in the United States military must therefore conform to international standards.


Strategic Computer Network Attack in the U.S. Military Today

The integration of information warfare in general and computer network attack specifically in the United States military structure is not new. Information warfare operation were carried out in both Operation Desert Storm (Iraq, 1991) and Operation Allied Force (Kosovo province, Yugoslavia, 1999) by the United States military. The question of whether the United States should adopt computer network attack is not considered here, since it already has been adopted and used to an extent. Only whether the Laws of Armed Conflict apply to information warfare and if so, the manner in which computer network attack should be deployed in accordance with the Laws of Armed Force are considered.

In the applicability of the Laws of Armed Conflict, the United States has not directly stated whether or not it considers information warfare governed by these agreements. The U.S. military has stated that it will deploy information operations in accordance with the Laws of Armed Conflict, indicating in that case that information warfare is considered armed conflict (U.S. Space Command). The issue has not been addressed in civilian sectors, for government agencies such as the National Security Agency and the Central Intelligence Agency.

U.S. diplomatic strategy concerning information warfare has also yet to be determined the long run. As a report from the Office of the General Counsel of the Department of Defense states, the United States has not yet addressed fundamental policy decisions about where its long-term interests lie in connection with the possible international legal restriction of information operations. On the one hand, there is an obvious military interest in being able to interfere with an adversary’s information systems, and in being able to protect one’s own. Used as an instrument of military power, information operations capabilities have the significant advantage that they minimize both collateral damage and friendly losses of personnel and equipment. Their use may avoid unwanted escalation of a dispute or conflict. They are relatively cheap and require much less in the way of forward basing, deployment, and logistical support than do traditional weapons and their delivery platforms. On the other hand, as the nation that relies most heavily on advanced information systems, the United States has the greatest vulnerability to attack. This concern would seem to drive U.S. policymakers to consider the merits of international restrictions on information operations. (pg)

The report goes on to discuss U.S. diplomatic policy in that past two years concerning information warfare. On a United Nations resolution, backed by Russia, calling on states to make official policy regarding dangerous information weapons, the United States has taken the position that it is premature at this point to discuss negotiating an international agreement on information warfare, and that the energies of the international community would be better spent on topics of immediate concern such as helping each other to secure information systems against criminals and terrorists (4)

The U.S. position as a result remains ambiguous. Policymakers have yet to decide if the potential harms to the U.S. information infrastructure outweigh the military advantages posed by computer network attack. An addition concern is the lack of law enforcement on the international level. Should the U.S. abide by legal restrictions on computer network attack, there is no guarantee that other states will recognize these restrictions. Considering the United States’ vulnerability to such an attack, policymakers’ reluctance to codify U.S. policy in this regard is understandable. As the world’s lone remaining superpower, however, the United States could greatly influence international law in this regard to its own advantage if the government acts before precedent is largely set.


The Applicability of the Laws of Armed Conflict

A first limitation placed on the international legal status of Computer Network Attack lies in the Laws of Armed Conflict. A primary dilemma involves whether Computer Network Attack and information warfare in general constitute actual warfare and, as a result, are limited by international restrictions on action during war. Each author presented here defines armed conflict in a distinct manner. This definition forms the basis for each author’s arguments and reveals his bias concerning information warfare.

Former National Security Agency attorney Lawrence Greenberg, in his opinion paper written for the National Defense University, bases his definition of warfare on three main characteristics: physical destructiveness, territorial intrusiveness, and the military traits of the target. Greenberg argues that information warfare does not sufficiently meet these criteria and as a result is not a form of warfare. For instance, the amount of damage attributable to an information attack bears little resemblance to the physical damage inflicted during traditional warfare (10). An information attack cannot be considered intrusive in the traditional sense given that cyberspace recognizes no boundaries (11). Since most of the targets in information warfare are civilian and not military, the last criterion of traditional warfare is also not reached (14). Instead, he argues that information warfare could be considered along the same lines as economic sanctions during peacetime, an action taken as a result of a state’s offensive behavior (xviii). A fundamental problem with this logic is that the military does not carry out economic sanctions; the same cannot be said for computer network attack operations. When considering his criteria for defining armed conflict, several other problems arise. The nature of a networked society and the plethora of civilian targets conflict with Greenberg’s argument that computer network attack may not cause as much damage as a physical attack. The choice of targets in a networked society could change that. For instance, the recent “ILOVEYOU” virus hit tens of millions of Internet users and cost over a billion dollars in damage (Denning). An attack against a stock market could cause more economic damage. The damage done to national security after a successful hit at a military website is likewise not so easy to repair. Greenberg’s second argument concerning lack of boundaries also encounters difficulties upon review. Cyberspace may not be contained in any physical realm with which international law is accustomed to dealing, but extending American sovereignty over the websites of American institutions, such as government and military sites, is within the range of current international law. The question of boundaries will be explored further below. Greenberg’s third criterion, civilian targets instead of military, seems almost inevitable in the post-Cold War period. The combination of diminishing military budgets, a strong communications industry that is reducing costs, and the military’s expanding communications needs means that military use of civilians satellites and networks makes the most sense. Today, 95 percent of U.S. military communications is routed through civilian communication lines, indicating the military’s strong dependence on the civilian sector (Arquilla and Ronfeldt, 178). A consequence of this is, of course, that any attack on a military network is likely to be also an attack on a civilian network. In another sense, Greenberg’s observation is a consequence of the post-Cold War world and globalization. The civilian communication sector is growing at a faster pace than the military sector and accounts for more networks. The law of averages states that a civilian target is more likely to be hit than a military one.

Richard Aldrich, an Air Force Staff Judge Advocate and associate professor of law at the United States Air Force Academy, uses an historical definition of armed conflict by consulting international treaties on war. The term is not specifically defined in the 1949 Geneva Conventions (Roberts and Guelff, 169-337). The term, Aldrich argues, was generally accepted to apply “wherever regular armed forces engage the regular armed forces of a foreign state or enter the territory of a foreign state without permission.” Like Greenberg, Aldrich emphasizes two characteristics indicating the physicality of armed conflict. “Engage” implies a physical meeting between armed forces. Aldrich also emphasizes the territorial question. Defining the territory the military is allowed to defend is difficult with the introduction of cyberspace. Since cyberspace is not a physical place, it is difficult to consider it part of the state. The websites of American institutions can fall easily under the traditional definition of territory; however, the websites of multinational corporations or non-governmental organizations with branches residing in multiple countries present a problem. Under this definition, computer network attack would most likely not be considered armed conflict; Aldrich, however, concedes that certain international obligations concerning the laws of armed conflict should be considered.

Using similar methods, Hilaire McCoubrey and Nigel D. White, both professors at the Centre for International Defence Law Studies at the University of Nottingham, come to a different conclusion. They describe that “international armed conflict involves resort by states to active and hostile military measures in the conduct of their international relations with intent to the attainment of policy objectives or defence against the same, whether or not a state of “war” is declared or recognized to exist” (McCoubrey and White, 194). McCoubrey and White present a perspective that concentrates more on the international legal aspects than on the military ones. While Greenberg and Aldrich are both lawyers and specialize in international law, they present a definite military bias, perhaps preferring the American deployment of information warfare, in Greenberg’s case unhindered by international standards of law. Under McCoubrey and White’s definition, computer network attack would certainly apply. Hacking into another state’s military computers can be considered an active and hostile measure. Given that McCoubrey and White do not have the two biases that Greenberg and Aldrich present, as the latter both consider first the military advantages of information warfare before the legal implications and both are Americans, their definition gives a more international perspective on the issue. All three are valid definitions. It is up to American policymakers to decide which best interpretation of international law.


Implications of the Laws of Armed Conflict for Computer Network Attack

In his article, Aldrich outlines three main principles of the Laws of Armed Conflict that apply directly to information warfare: the principles of military necessity, humanity, and chivalry. The Department of Defense report on the international legal issues of information operations details other concerns in international law, including the definitions of combatants and noncombatants and the role of neutral nations; however, these issues fit under the umbrella of one of these main principles.

Principle of Military Necessity. Customary international law provides that enemy forces during war may be attacked at all times to achieve the defeat of the enemy. In the report prepared by the Department of Defense, it is argued that “civilians and civilian property that make a direct contribution to the war effort may also be attacked, along with objects whose damage or destruction would produce a military advantage because of their nature, location, purpose, or use” (5). By extension, civilians who contribute little or nothing to the military effort and whose destruction would provide little military gain are exempt from deliberate attack. In terms of information warfare, this raises the question of who is and who is not a combatant. A civilian attacking foreign computer networks, perhaps without her government’s backing, would, under the Department of Defense’s definition, be a legitimate target. This certainly stretches the definition of traditional armed conflict, in which legal combatants are assumed to wear distinctive uniforms and be members of the regular, trained militia of the country. In fact, if the perpetrator indeed did not have the backing of the government, many international lawyers consider this more an act of cyberterrorism than one of information warfare between two states.

The principle of military necessity also affects the extent to which information warfare may be used. In suggesting strategies of using information operations, Colonel Owen Jensen describes the importance of the Principle of Decapitation: Cut or deny all the enemy's information-transfer media-telephone, radio frequencies (RF), cable, and other means of transmission. Sever the nervous system. Deny, disrupt, degrade, or destroy every transmission. Stop all "gray system" access. Close off to the enemy all third-party communications satellites (COMSAT), whether they belong to international consortia or to commercial enterprises or are assets of uninvolved nations. (Aldrich)

While certainly achieving the enemy’s defeat, the Principle of Decapitation, Aldrich argues, also probably violates the principle of military necessity, by overstepping the bounds of attacking only enemy military and violation the rights of neutrals. The rights of neutrals will be discussed further with the principle of chivalry.

A final contribution of the principle of military necessity to the legal restrictions on information operations is that, like international law, military necessity permits everything not specifically prohibited by the Laws of War. In the above scenario described by Colonel Jensen, the military actions taken are not themselves in violation of international law. Only their effects are. The impact of this should influence U.S. policy with regard to information warfare. In instances where military necessity is proven and other international laws are not violated, information warfare has no limitations. This, however, applies to U.S. defense, as well. No limitations govern the actions of other states in this regard, either.

Principle of Humanity. The principle of humanity applies just as strongly as the principle of military necessity to the conduct of information operations. Many of the effects discussed above in violation of international law relate to the principle of humanity. Aldrich defines the principle of humanity as the prohibition of “the employment of any kind or degree of force not necessary for the purposes of war, that is for the partial or complete submission of the enemy with the least possible expenditure of life, time and physical resources.” In an oft-feared example, hacking into American networks to shut down the stock market would violate the principle of humanity. The Department of Defense report adds to this the idea of proportionality, in which a civilian target, such as a bridge or, in information operations, a civilian-run network, may be destroyed or damaged if the military benefits are proportionally larger than the civilian damage (5). This fits in neatly with the U.S. reliance on civilian networks: any attack aimed to shut down U.S. military communications would most likely damage civilian networks disproportionately. In legal theory, the enemy ought to attack, to his best ability, only military communications. In reality, this is very difficult, and the enemy may not observe such niceties.

Compared to other forms of warfare, information operations may be viewed as the one form closest to complying fully with the principle of humanity. Information operations rarely cost lives; the main drawback to the enemy is loss of time, money, and information. In this regard, information operations would be preferably to any physical armed conflict. The conduct of the operations and not the operations themselves determine their legality or illegality.

Principle of Chivalry. The last main principle of the Laws of Armed Conflict to affect the conduct of information operations is the principle of chivalry. Under the principle of chivalry, those in conflict ought to respect the formalities and courtesies of warfare (Aldrich). This principle is mostly considered in regard to the use of deception and the rights of neutral states.

International law makes a distinction between the use of deception in a ruse and in perfidy. In a ruse, the attacker does not rely on protected international symbols or signs to defeat the enemy. International symbols include the Red Cross and the white flag of surrender, among others. Perfidy, however, includes the use of such symbols to gain a military advantage over the enemy and is not allowed under international law (1977 Geneva Protocol I, in Roberts and Guelff, 409). The impact of this aspect of the principle of chivalry seems to be the least significant for information warfare. An email understood to be sent by or on behalf of an organization such as the Red Cross that contains a virus would be an example.

The rights of neutral states, on the other hand, are among the most significant impacts of international law on information warfare. Any neutral state is considered immune from belligerency as long as it does not aid either side; should a state be unwilling or unable to prevent aiding one belligerent over the other and still claims neutral status, the unaided belligerent has the right to attack (Department of Defense, 6). This principle applies easily in land and sea wars; however, in cyberspace, as previously argued, national boundaries are ill-defined, if defined at all. Should the attacker use an Internet Service Provider owned by a foreign corporation or an ISP based out of a neutral country, should the neutral country be open to retribution by the defending state? Complying with the status of neutrality could mean cutting off communications with both belligerents completely, an act that could prove detrimental to the neutral’s economy and citizenry. In that circumstance, the neutral country would be unwilling, and most likely unable, to prevent communications from one belligerent to another. U.S. policymakers must take the difficulties posed by the rights of neutrals onto consideration when forming information operations policy.


The Impact of the Laws of Armed Conflict on U.S. Computer Network Attack

When formulating U.S. policy, American decision-makers must first determine whether or not to apply the Laws of Armed Conflict to information operations. The importance of this decision is clear: in a society as legally-driven as the United States, any policy must have clear legal justification to be accepted. Thus, domestically the United States must define whether or not information operations are armed conflict, and must define them in terms acceptable to the public. The impact of public support on policymaking during previous wars has been considerable: witness Vietnam and the conflicts in the Persian Gulf and Kosovo, to a lesser extent. Should it come to light that the United States committed illegal acts during warfare, public opinion could sway public policy. In contrast to Greenberg’s sanctions argument, public opinion is not likely to regard information operations as a peaceful policy. Fear of the consequences of potential computer network attack places information warfare, the name itself indicating a threat, as a danger to personal and public safety. The public will likely not support defining information operations of this magnitude as a “peaceful” action like sanctions when defining it as such would mean that other countries can take this same “peaceful” action.

The United States, while claiming sovereignty over its people and its territory, has also a definite interest in abiding by accepted international law, even without strong international legal enforcement. As a world leader, the United States’ actions can easily set an example for other countries to emulate. To a limited extent, this could set limits on what actions other countries could take. The United States is at a certain advantage in the international situation today. Maintaining the status quo is in the country’s best interests.

A final consideration for U.S. policymakers in defining the nature of information operations is the impact on U.S. computer network defense. The United States has military and civilian sectors that are the most vulnerable to computer network attack in the world. Should policymakers not define information operations as armed conflict, information warfare against the United States would face few, if any, legal restraints at the international level. While legal restraints would probably not inhibit all states from resorting to illegal information warfare, it would stop some. Additionally, defining information operations as armed conflict gives the United States moral standing for retribution against the attackers. If the attack can be traced to a foreign government, the United States can defend itself by attacking that country. The U.S. military would most likely take this action no matter the official American definition of information operations, but the advantage is more aesthetic than real. Demonstrating an effort to restrain information operations on an international level would put the United States in the position of the offended and not the offender.

Should U.S. policymakers define information operations as warfare, the Laws of Armed Conflict would restrain certain aspects of U.S. information operations strategy. The first restraint would be on whom is allowed to carry out information operations. Armed conflict is accepted as contention between the regular militia of two belligerents. This would imply that the military, in the case of the United States, the Space Command, has the right to carry out information operations. Civilian agencies, however, would be excluded under this definition. The use of computer network attack for the National Security Agency and the Central Intelligence Agency has certain advantages for each agency, considering they each specialize in information gathering. Restraining their use of information operations could be detrimental to national security

Another restraint concerns what and who is targeted. The Laws of Armed Conflict mandate that targets have mainly a military purpose. The state of technology and the domestic interaction between the military and civilian communications sectors may render this principle obsolete. Disrupting communications for the enemy could mean damaging main power sources in the country electronically. This question is considered many times in conventional weapons use as well. The difference between using a bomb dropped from a plane and using a computer virus to damage a power plant in a city is not necessarily the issue: they both cause the same damage. The new side of this issue with information operations is the distinction between civilian and military combatants. The principle of humanity protects most civilians from attack; however, if a civilian is the attacker, this distinction presents a problem. If the military uses a civilian target, such as certain communications lines, this distinction is also stretched. During conventional warfare, judgment calls are made regarding the applicability of proportionality and the principle of humanity. Damage from, for instance, bombing a bridge can be repaired quickly, though. Damage inflicted on a communications network is not as easily repaired. Judging proportionality in this case requires taking consequences beyond the immediate effects into consideration.

Policymakers must address the question of territory and its definition within cyberspace. Domestically and internationally this is perhaps the most important decision to be made. An international agreement on this problem is necessary for effective enforcement of trade laws, trials of cybercriminals, and instances of armed conflict.

A final consideration for policymakers is the method of information operations and issues related to this. This includes the use of foreign Internet Service Providers to launch attacks against another country. For this issue, policymakers are almost forced to cooperate with the international community in grappling with this distinction. The development of the Internet Tradition demands that the issues of territoriality and neutrality be addressed in a manner consistent with international standards; however, the development of the Internet renders this nearly impossible.


Conclusion

Rapid advances in information technology over the past decade and more force policymakers to reconsider standards set in the United States over the past two hundred years. The advent of the Internet and the development of information warfare require a paradigm shift in military thought. The current revolution in military affairs is not simply in weaponry or strategy; it is also in the fundamental concepts of war and armed conflict, in defining what is military and what is not, in outlining what is and is not acceptable during war. War can now be bloodless; it also now has the capability of rapidly spreading to every country via electronic mail, disrupting and potentially destroying the world economy. Traditional concepts of “territory”, “war”, “civilian”, and “neutrality” could be rendered obsolete with the advances in information technology. As the world economic leader and strongest military power, the United States should take the initiative in redefining these concepts and applying them to international law.

On balance, acknowledging computer network attack as a form of warfare best serves the United States’ interests. Concerns for the integrity of the nation’s information infrastructure should outweigh the potential for development of information warfare as a civilian action. The United States is vulnerable not only to computer network attacks from other states, but also, in perhaps a more likely scenario, from hackers and cyberterrorists, individuals who are not bound by the Laws of Armed Conflict. Respecting the Laws of Armed Conflict in these situations can place the United States in a good diplomatic relationship with other countries, whose cooperation may be necessary to bring the perpetrators to court. Retribution for these armed attacks can also be more justified from a legal standpoint if information warfare is considered to be governed by the Laws of Armed Conflict. The rapid development of information technology compels the United States to cooperate with other countries to resolve these issues and develop a new international standard acceptable to all.



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