Non-Lethal Warfare

-Ajay Singh, Research Fellow, IDSA



The last decade has been significant as far as military technology is concerned. The Cold War years were characterised by hostility between the former USSR and the USA in the form of the Warsaw Pact and North Atlantic Treaty Organisation (NATO) alliances. The end of the Cold War, on the one hand, suggested that the threat of a large-scale global war had subsided. On the other hand, the Persian Gulf War showed that armed conflict remained a reality. In the post-Cold War years, there has been a shift in the nature of armed conflict that is likely to be encountered by a large number of nations. The reasons for this are many, but essentially what we witness today is a relative growth of conflict at the sub-state and inter-state level in the form of irregular warfare. In most of these cases, the forces pitted against each other are not regular militaries. In fact, more often not, the state's regular forces (military, paramilitary, or police) have to combat organised militant groups and terrorists. This usually falls under the law enforcement role when it is within a state, or peace-keeping/peace-making when external inputs are required such as in UN missions. In both cases, there is a requirement to follow the principle of minimum force. It is difficult to use minimum force when dealing with forces armed with lethal weapons on either side of the conflict, and there is an inherent problem here that leads to questions of human rights excesses on the part of the peace-restoring forces.

Higher up the spectrum of conflict where regular military forces are involved in fighting each other, the requirement of minimum force is replaced by the law of armed conflict that espouses the principles of proportionality (of force applied) and military necessity. While these have been in acceptance for some time now, certain factors have altered the perspective. With the growth of the media into the realm of satellite television, there is an increasing awareness in the public domain of events that might be taking place across the globe that leads to what is termed as the "CNN effect." Governments and military forces have to contend with this exposure, and face pressure to adhere to the normative response in armed conflict. At the same time, and particularly so in democracies, there is an increasing abhorrence to suffering of casualties in one's forces and also of civilians and their property. The demand for low collateral damage has spurred advances in precision weaponry, which consequently reduces own casualties due to lesser exposure to the enemy as the number of attacks to achieve the objective reduce. While this has driven some of the developments in military technology, it has also rejuvenated the debate on non-lethal weaponry that is seen to fulfil some gaps in capability of security in the light of the roles in irregular warfare that they have been asked to perform in recent years.

Non-lethal weapons have generally been understood as a class of weapons that are designed to minimise fatalities and damage to material while causing incapacitation. While there are some definitions that are more descriptive, in essence they all deal with non-lethal weapons in a similar manner, that is weapons "designed" to produce non-lethal effects wherein death and severe permanent disablement to personnel are unlikely.1 It should be pointed out that this understanding itself is not fully adequate. Some weapons that are proposed to be included in this category are in fact not authorised under international law. Additionally, some non-lethal weapons are not truly non-lethal in many employment scenarios. An example is a microwave beam that may be used to destroy electronic circuits in communication systems might also be aimed at an aircraft in flight leading to a crash due to malfunction in the flight control system. The inaccuracy in classifying these weapons has prompted the legal minded to term them as less-than-lethal weapons. Most of these definitions appear to miss a crucial point. Inasmuch a weapon designed to produce non-lethal (or less-than-lethal) effects can actually lead to lethality on employment, there could be other weapons and technology which though not explicitly designed for non-lethal effects (in the sense defined) might produce non-lethal effects by virtue of their employment. The employment of weapons needs to be seen in the light of the objective that is targetted for neutralisation. An example could be a bullet or a missile aimed at a critical link of a power generation system, which in fact leads to failure of the whole system on account of associated effects in the target system such as a short circuit. Another aspect that needs to be bought out is that when we refer to non-lethality, it should be limited to human life and not extended to include material or property in order to achieve some degree of focus and clarity. Life once lost cannot be replaced while material can be, and, therefore, while destruction of material merits concern, it should not be simply clubbed with the concern for minimising the horrors of conflict faced by humans.

Non-lethal warfare should then be understood as consisting of those weapons, technologies, and techniques that incapacitate humans while producing minimum fatalities and permanent disabling effects on human life either by discriminate non-lethal design or targetting or a combination of both. A closer examination will reveal that the aim of the weapon, whether it is lethal or non-lethal is to incapacitate the human and make him unable to take appropriate action. Action is the output part of the Information-Decision-Action (IDA) cycle that represents military activity (and most civilian as well). Lethel or non-lethal could be applied to any part of the IDA cycle to affect the action, whether it is to deny information or influence decision making or directly concern the action segment itself. The important difference lies in the philosophy of the non-lethal weapon in that the resultant incapacitation should not lead to human fatality or permanent disability (of the human). Non-lethal warfare, therefore, could be conducted against humans or the materials that support them in the IDA cycle, whether it is in aircraft, truck, tank, or ship.

The concept of non-lethal weapons is not new. History has recorded instances of use of weapons and techniques of war-fighting that did not cause lethal effects ranging from the use of smoke for purpose of concealment of some form of biological warfare that caused illness leading to incapacitation (sometimes permanent disability). These were regarded as weapons to be employed in war without much thought given to whether it was humane or not. Consequently, there was little effort to identify these weapons on the basis of the degree of lethality caused. Although some change in this perception occurred in the 19th century, it took the horrors of World War I to bring home the reality of suffering caused by weapons that did not produce instant lethal effects. The drafting of codes of conduct of war to limit human suffering amongst the military and to shield civilians from the effects of war was pursued with greater commitment than before. Another outcome of World I was that military technology of chemical weapons was passed on to the police forces for utilisation in law enforcement duties, particularly in activities like riot control, as a result of recognition of the potential of chemical weapons in non-military missions.

The use of non-lethal weapons by military forces has been rather limited owing to lethal constraints concerning the use of force in war and technologies available for employment in the battlefield. A crude form of non-lethal technology was seen in the employment of Agent Orange by the US forces in Vietnam.2 This caused defoliation without direct effects on human life. In the Falklands War of 1982, the Royal Navy reportedly employed low energy laser beams to distract Argentinian pilots attacking their ships.3 Of course, while this has been cited as an example of use of non-lethal weapons, it is not clear if the pilots suffered permanent disability to their eyes. By the time of the Persian Gulf War, military technology had advanced to a level where the employment of non-lethal weapons was reportedly being considered in exotic forms, ranging from electromagnetic pulses for destruction of electronic circuits to chemicals that would break up aircraft structures. Two cases were publicly reported as having been used during this war. The first concerned low energy lasers mounted on armoured vehicles and infantry rifles. These were supposedly meant to counter the enemy's target acquisition systems. The second was the use of carbon-fibre strips that were used in Tomahawk cruise missile for disruption of Iraqi power generation by causing short circuits.4Since the Persian Gulf War, there has been an increased interest in non-lethal weapons and it may be useful to consider some of the technologies and weapons that go under the rubric of non-lethal warfare.

Non-Lethal Weapons and Technologies

One of the technologies that are being developed for use in non-lethal warfare deals with acoustics. The frequencies in the electromagnetic spectrum used for audio reception by the human ear lie between 20 Hz and 20kHz. Within these frequencies, any increase in the intensity would lead to eardrum damage. Below this band of frequencies, experiments are being conducted to exploit what is known as the infrasound range of frequencies. Infrasound frequencies with high intensity might be used in the anti-material (AM) mode wherein physical structures such as buildings could be affected by setting up of vibrations to an extent that damage could result. These frequencies could also be used in the anti-personnel (AP) mode to affect the internal organs of the human body to cause disorientation (when applied to the ear,) nausea, vomiting, and bowel movements.5 A more sophisticated system in the AP mode could be the employment of stun grenades that affect the target with the physical force of sound waves. It has been suggested that such weapons may be employed for crowd control and counter-terrorist operations.

The area of biomedical research has received attention owing to the potential of biological agents in non-lethal warfare. Much of the attention is on account of the legality or rather illegality (as is more true) of using these agents in view of the Biological Weapons Convention (BWC). The Los Alamos National Laboratory has reportedly carried out research in this field and discovered (or developed) a bacterium that degrades a specific material used in many weapon systems.6 More commonly known as biodegrading organisms or microbes, these literally eat away the system and effectively disable it. In the anti-personnel mode of employment, non-lethal disease organisms can deter or incapacitate people. Bioengineering and psycho-pharmacy are also fields that seek to exploit the vulnerabilities of the human brain through genetic engineering techniques and behaviour-affecting substances that perhaps reach into areas with potentially dangerous social consequences. Lower down the scale are biochemical substances that can cause incapacitation. Most people are familiar with tranquillisers, but these can also be administered to unwilling subjects by a side carrying out non-lethal warfare. These and similar drugs can be used with dart guns, not different from the poison arrows that most people normally only read about storybooks. They can also be placed in ventilation passages and air conditioning ducts with more widespread effects. While this can serve the state for its law enforcement duties, it needs to be remembered that such techniques can also be employed by people on the other side of the law with serious results like the Sarin nerve attack in the Tokyo subway not so long ago.

Chemical warfare is also not new, and notwithstanding the Chemical Weapons Convention (CWC), the techniques and chemical substances for use against humans will continue to be in existence, at least for some time in the future. The use of chemical substances for controlling crowds and riots has been going on for a number of years in the form of tear- gas, which can be classified as non-lethal warfare, and remains viable to this day. The use of chemical substances has seen technological advancements in the recent years, with research being conducted in development of adhesives, corrosives, foams, lubricants, etc. Adhesives are similar to the superglue that is commonly used in domestic applications and can be used against personnel or material. These contain chemicals that rapidly glue materials, thereby causing immobilisation. Of course, personnel affected in this manner would need to be unglued once the threat is over, and that may be slightly troublesome! For that reason these adhesives could be employed in a better manner against materials such as military vehicles and aircraft, especially if they can be sprayed from the air. Foam may be sticky and viscous or dense and bubbly and cause similar effects by immobilising people and may be preferred for the anti-personnel role. This was reportedly deployed (perhaps not used) by US forces in Somalia, and was developed by Sandia National Laboratory to counter nuclear terrorism.7

Corrosives that are being developed include liquid metal embrittlers and supercaustics. Embrittlers change the molecular structure of metals and alloys, weakening them, which may lead to failure. These substances are in liquid form (an example is mercury), and are difficult to detect once applied to a metal surface. They would have great utility in covert operations and sabotage. Supercaustics are generally bases (supercorrosives are also considered as supercaustics by some and are acidic in nature) that affect organic compounds such as glass, rubber, and plastics. Another area of research and possible application pertains to anti-traction technologies that make use of superlubricants. These superlubricants could be employed on road surfaces that would make movement of vehicles (which require roads) difficult. The effects of superlubricants may be neutralised to an extent by spraying substances like sand over the affected surface, but this may not possible in the case of runways required by aircraft without causing ingestion damage to the engines. The advantages of mechanisation for the land forces has also given rise to vulnerabilities to non-lethal warfare techniques that affect combustion in engines of the vehicles. Combustion alteration technologies include chemical additives that contaminate the fuel, leading to malfunction of the engine. Materials that clog air filters have also been suggested to achieve the same aim. It needs to be pointed out that the vulnerabilities of aircraft to these engine disabling technologies is far greater since propulsive power is critical to their operation as compared to surface vehicles.

The electromagnetic spectrum has been exploited extensively to support lethal war-fighting for decades. The growing dependence on the electromagnetic spectrum of sensors, weapon systems, and communications has increased the vulnerability of the users of this spectrum to electronic warfare. Electronic warfare techniques en masse would come under the cloak of non-lethal warfare, but for the present it may be useful to examine the advances made in the spectrum where technologies are being developed from the outset with non-lethal capacity. In the Gulf War of 1991, electric power disruption munitions were used to cause short circuits in the power lines and distribution points. High microwaves may be employed as directed energy weapons, which penetrate unshielded electric systems, causing damage. It has been reported that high power microwave warheads have been under development in the USA for a number of years, and might be used with cruise missiles. The production of electromagnetic pulses (EMP) as a result of nuclear explosions has been known for some time, but efforts are under way to achieve the generation of EMP through non-nuclear sources. Besides this, research is on to develop such a weapon for use to incapacitate people, which is similar to electric guns that are commercially available at present.

The use of lasers as non-lethal weapons has been the subject of some debate since even some low-powered lasers can cause permanent effects such as blindness. They have been used in the Falklands War of 1982, and also reportedly by the Soviets in Afghanistan. While laser goggles can be used as a counter-measure, there have been developments in the field of low energy lasers that oscillate their output through different wavelenghts that makes it extremely difficult to counter. Besides military use, these types of lasers do have utility in counter-terrorist operations. Another use of light is in the form of strobes to cause vertigo, nausea and disorientation when high frequency lights are flashed at or near brain-wave frequency. This may find application in a wide range of missions from military to law enforcement.

In recent years, information has come to acquire great importance in almost all spheres of human activity. This is likely to increase in the future. The potential for non-lethal warfare is tremendous in this field, and can be manifested at various levels. The most commonly perceived is the damage that can be caused to computer systems through insertion of various viruses that alter or even destroy the stored information. Similarly, the use of hidden codes on microprocessors that could be activated under discrete instructions leading to malfunctions is a reality.8 To disable or disrupt the human decision making system, media campaigns (psychological) might also be resorted to to shape news and opinion growing out of the news. Part of this facet of non-lethal warfare is the ability known as voice synthesis, wherein a voice can be cloned and messages broadcast for a particular purpose. Another dimension that is relevant is the use of public laws for the purpose of restricting information or its related systems. Both these may be international or national in character. The US laws regarding protection of intellectual property rights are a case in point. In fact, information warfare deserves a separate subject in its own right but does also form part of non-lethal warfare. Non-lethal warfare also includes kinetic weapons that rely on the energy imparted by motion such as rubber bullets that have been used by police forces. These reduce the risk of fatality while causing incapacitation of humans and damage to material. Entanglers may also be employed in the form of nets, meshes, etc. that can arrest the movement of vehicles or personnel.

Legal Issues in Non-Lethal Warfare

Non-lethal warfare appears at first glance to be an oxymoron, since lethality is so closely associated with perceptions of warfare. Lethality in war, however, has generally not been pursued in the extreme sense of the term, and over the years there have been conscious efforts to guide the conduct of war along humane lines. The spirit and (and letter) behind the laws governing conflict and weapons has been guided by the concern to lessen the extent of human suffering. Some of the major laws of modern times that are relevant to the legal issues of non-lethal warfare are the Law of Armed Conflict (LOAC), BWC, CWC, and the 1980 Inhumane Weapons Convention (IWC).

The international law of armed conflict resulted from the restriction imposed by the necessity of harmonising the aims of war with the laws of humanity. While the laws concering use of military force have been understood in various forms over the centuries, the modern LOAC owes much to the Declaration of St. Petersburg in the late 19th century, which stated that the only legitimate object of war was to weaken the military forces of the enemy. The document spelt out that it was sufficient to disable the maximum number of men, and this object would be exceeded by employment of arms that uselessly aggravate the sufferings of disabled men or render their death inevitable.9 The Hague and Geneva Conventions that dealt with the laws and customs of war on land and treatment of civilians and prisoners of war followed this declaration. The world community thus made definitive efforts to make war more fair, just, and humane after development in weapons technology had overtaken the earlier concept of "righteous" war, increasing the level of suffering. In fact, the 1907 Hague Convention specifically dealt with the mitigation of unecessary human suffering. Another concern has been the protection of civilians from the effects of war, which essentially means that weapons must be employed in a discriminate manner that does not cause non-combatant casualties. The principles of military necessity and proportionality have arisen from the codification of the LOAC and guide the application of military force from the point of view of the objective as well as the quantum of the effort.

The LOAC has been a springboard for the development of non-lethal weapons technology since non-lethality by definition aims to minimise fatalities and permanent disabilities. By this yardstick, non-lethal warfare should actually represent a shift to a "clean" war where people do not get hurt grievously, and, therefore, should be encouraged from that angle. While this may be true for a number of weapons and technologies, there are concerns focussed at those weapons and technologies that might cause more than just temporary effects despite claims to the contrary. Laser weapons are an example that could lead to permanent loss of sight. By adopting an inclusive definition of non-lethal warfare (as suggested earlier) that refers to design capability as well as targetting intent, some of the doubts regarding the dual use of non-lethal weapons may be addressed. Even then, the issue that some of the technologies under development might violate the BWC, CWC, or IWC needs careful consideration. It is believed that countries, notably the USA, have exploited the loopholes in these Conventions to develop biological and chemical weapons under the garb of non-lethal weapons, and, therefore, there has been a fair degree of opposition to these efforts. Whether these loopholes are present by design or default is a pertinent question. An example is that the CWC does not permit use of riot control agents as a method of warfare, but it is believed that the US would use them in peace-keeping operations and law enforcement operations. Similarly, if some biological agents violate the BWC, there is general concern about the future of such Conventions. Nevertheless, it needs to be kept in mind that non-lethal warfare promises advantages for a range of military and non-military options, provided, of course, the letter and spirit of international law are followed. It should also be pointed out that the international laws governing weapons and conflict need to be suitably modified to include the weapons that fall under non-lethal warfare. Besides the emphasis on the humane dimension, some thought is also required to see if warfare itself needs further interpretation since non-lethal warfare could easily be conducted without a state of war being declared formally.

Impact of Non-Lethal Warfare

One role that has great application for non-lethal warfare is special operations. Although special operations started as being special and apart from conventional warfare, the sheer extent of these operations had made it necessary to deal with them almost on par with conventional war. Special operations are conducted in politically sensitive scenarios, where application of force is often to be kept at the minimum destructive level. The two main missions in special operations for military forces using non-lethal warfare techniques could be counter-insurgency and peace-keeping/peace-making. A wide range of non-lethal weapons could be gainfully employed in both scenarios. An area of overlap would be law enforcement duties where police forces could utilise these weapons much in the same manner as teargas has been used for decades. Non-lethal weapons hold promise for being the weapons of choice in these situations, particularly when the opponents are not well endowed with destructive capacity.

An aspect that emerges from non-lethal warfare techniques is that the role of intelligence (which is crucial to war-fighting) needs greater attention.10 This is because if the effects of non-lethal weapons are essentially less destructive, then there will be a challenge for the military planner since he may not know if the previous attempt (for example, disabling a computer network) has succeeded or not. This leads to the question of how much effort should be put in to neutralise a target system. The relative paucity of battle damage assessment makes the task quite difficult and might prompt adoption of lethal weapons. The example of the Gulf War of 1991 needs to be highlighted where the non-lethal strike on the Iraqi electrical power generation system through carbon-fibre filled cruise missiles had to be followed up by conventional destruction by lethal weapons.

In the event of the opposing force being equipped with destructive weapons, as would be the case in conventional war, then non-lethal weapons might have to be viewed differently, as add-on options rather than the main choice for the military commander. In conventional war, non-lethal weapons could also be employed independently, such as denial of runways through anti-traction technologies rather than runway penetration bombs. While at the tactical and operational level of war, non-lethal weapons essentially expand the range of options available, their impact on the strategic level merits consideration. Much of what goes as non-lethal warfare actually falls shorts of the conventional understanding of war. Information warfare is an example. This in itself has certain ramifications. A country might perceive an attack on its information networks as war and respond on another plane, which actually lowers the threshold of war as compared to warfare with physical destruction. Another is that clandestine operations could be conducted without the victim knowing who the aggressor is or what the intent is, and, therefore, would largely be forced to remain defensive. In such situations, strategic paralysis might be achieved with similar effects as those associated with nuclear asymmentry. This has the potential to lead to strategic instability and is important to understand.

Arms control negotiators will have to broaden their scope of operation to include non-lethal weapons in a more substantial manner, than simply trying to restrain these technologies because of a possible technological race in such weaponry or its resultant fall-out on proliferation which could be the chosen route for countries that are not capable of this technology. Some of the issues that need consideration could be its effect on strategic stability and whether non-lethal technologies can be controlled. The control referred to would include measures with respect to non-state actors since they could constitute a significant threat.



1. Wing Commander E.E. Cassegrande, Non-Lethal Weapons: Implications for The RAAF, (Fairburn: The Air Power Studies Centre, 1995), pp. 3-6.

2. Malcolm Dando, A New Form of Warfare: The Rise of Non-lethal Weapons, (London: Brassey's 1996), p. 74.

3. Cassegrande, n. 1, p. 9.

4. Ibid.

5. Maj Jonathan W. Klaaren and Maj Ronald S. Mitchell, "Non-lethal Technology and Airpower: A Winning Combination for Strategic Paralysis," Airpower Journal, vol. IX, SE Special Edition 1995, p. 45.

6. Dando, n. 2, p. 15.

7. Ibid., p. 18.

8. Winn Schwartau, Information Warfare, (New York: Thunder's Mouth Press, 1996), pp. 254-264.

9. Maj Joseph W. Cook III, Maj David P. Fiely, and Maj Maura T. McGowan, "Non-lethal Weapons: Technologies, Legalities, and Potential Policies," Airpower Journal, vol. IX, SE, Special Edition 1995, p. 79.

10. See Capt Edward P.O' Connell and Ist Lt John T. Dillaplain, "Non-lethal Concepts: Implications for Air Force Intelligence," Airpower Journal, vol. VIII, no. 4, Winter 1994, pp. 26-33.