In fighting the Indochina war, the United States has made extensive use of two chemical agents: tear gas and herbicides. As debate on the Geneva Protocol banning chemical and biological warfare continues within the U.S. Senate and the Administration, two highly charged issues-Vietnam and man's destruction of his environment-are likely to merge. For it is the Administration's contention that the United States should ratify the Protocol with the understanding "that it does not prohibit the use in war of riot-control agents [tear gas] and chemical herbicides." A large number of Senators, however, consider that the Protocol prohibits the use of both, and feel that the Administration understanding dilutes the significance of U.S. ratification. Consequently, the members of the Foreign Relations Committee are not likely to vote the Protocol out of committee in its present form. And until the President replies to their criticism it appears that no action will be taken on it.

Although debate both within the Administration and before the Senate Foreign Relations Committee has centered around the wording of the Protocol and how it is to be understood, partisans on both sides of the question admit that the issues involved are considerably broader and more complex. In addition to the question of the use of herbicides and tear gas in South Vietnam, the progress of current chemical and biological warfare discussions at the Conference of the Committee on Disarmament in Geneva may hinge on the outcome of the current "understandings debate" and the ultimate fate of the Protocol.

To date, the Nixon Administration has compiled an excellent record in limiting chemical and biological weapons. In November 1969 the President reaffirmed the renunciation by the United States of the first use of lethal chemical weapons and went beyond previous policy statements by including incapacitating chemicals as well. The President also unilaterally renounced all possession and use of biological weapons even on a retaliatory basis and went so far as to impose limitations on research in this field. In February 1970 the President extended these renunciations to include toxins (biologically produced chemical agents). Elaborate plans for destruction of existing stocks of various agents are presently being put into effect.

After the President submitted the Geneva Protocol to the Senate in August 1970, the Military Assistance Command in Vietnam ordered an end to the crop destruction program and a phase-out of the defoliation program. The momentum of this sequence of moves has contributed significantly to international efforts to reach agreement on prohibiting chemical and biological warfare. Much of this momentum will be threatened should the President be unable to obtain ratification of the Geneva Protocol or if the ratification should be obtained with understandings or interpretations which would bring the United States into dispute with many of the nations already parties to the Protocol.

Ironically the United States first proposed the Geneva Protocol in 1925 and now stands as the only major nation which is not a party to it. The substantive provisions of the Protocol read as follows:

Whereas the use in war of asphyxiating, poisonous or other gases, and of all analogous liquids, materials or devices, has been justly condemned by the general opinion of the civilised world; and

Whereas the prohibition of such use has been declared in Treaties to which the majority of Powers of the world are Parties; and

To the end that this prohibition shall be universally accepted as a part of International Law, binding alike conscience and the practice of nations;


That the High Contracting Parties, so far as they are not already Parties to Treaties prohibiting such use, accept this prohibition, agree to extend this prohibition to the use of bacteriological methods of warfare and agree to be bound as between themselves according to the terms of this declaration.

The Protocol was submitted to the Senate for advice and consent in 1926. After extensive lobbying by the U.S. Army Chemical Service, chemical manufacturers and veterans' organizations and others, it was sidetracked and never brought to a vote. It was returned to the President as part of a housecleaning effort during the Truman Administration many years later. No further action was taken until it was resubmitted to the Senate by President Nixon.


Although much could be said about the legal interpretation of the Protocol, the history of negotiations indicates that it is not possible to come to a definitive legal conclusion. Therefore, it seems more important to evaluate the alternative understandings on the basis of their contribution to the national interest The following components of U.S. interests must be considered: the military consequences of alternative policies, both now and in the future; the impact of the current understanding on the intrinsic strength of the Protocol as an arms-control mechanism; the impact of the current understanding on other U.S. policies and objectives ; and finally, but most significantly, the ethical and moral considerations.

Despite the American use of tear gas in Vietnam since 1964 there has been no systematic study of its utility in that country. (President Nixon recently ordered such a study but results are not expected until early 1972.) Almost all the data presented on the subject, both pro and con, have been anecdotal, and in Vietnam anecdotal information can be found to support or refute almost any contention. Clearly, in some circumstances, tear gas has proven to be operationally effective. Military commanders have noted that the use of tear gas had some beneficial effects initially, but has had less effect as enemy forces have become increasingly familiar with the tactic. Tear gas cannot be used effectively against disciplined armies provided with gas masks except when surprise plays an important role. Masks in use by the National Liberation Front (NLF) in South Vietnam include the Soviet Shlem mask, a Chinese mask and various field expedients. It is well within the logistical capability of the NLF and North Vietnamese Army (NVA) to provide masks, and recently, according to one U.S. military commander in the Delta, almost all main-force enemy troops have been so equipped. Despite its acknowledged utility in some circumstances, the use of tear gas in Vietnam has recently decreased to only a small percentage of the previous rate.

A desire on the part of the United States to keep options open for the use of tear gas and herbicides implies that these weapons will be more useful to the United States than to any potential enemy in future wars. Many military experts have questioned this assumption. First, in view of the superiority of the United States over potential enemies in conventional warfare it is doubtful that the use of tear gas or herbicides would markedly change any balance of military power. Second, enemy use of such weapons against the United States or its allies might well create as many difficulties for the United States as its own use would impose on the enemy.

In guerrilla or insurgency warfare, where the United States would most likely find itself in the semi-static counter-guerrilla role, gas would probably be a tactical asset to the guerrilla because of his greater mobility and lesser vulnerability to surprise. Gas has considerable potential for use in situations where a guerrilla force surprises and attempts to overrun a fixed defensive position. Tear gas was used for this purpose in a recent successful attack on a U.S. fire support base in Vietnam. It is unlikely that it will play a significant role in major power confrontations or large-scale conventional wars. Certainly American use of gas would be precluded altogether if allied nations interpreted the Protocol to prohibit such use.

Chemical herbicides are used in war for defoliation and for crop destruction. Defoliation is used to facilitate observation of enemy troop movements and to deny areas to such troops. In cases of defoliation for observation purposes, once an area is defoliated and while it is undergoing regular surveillance, it is unlikely that the enemy will use it. There are frequently many alternative routes by which guerrillas or other forces can reach most destinations, particularly in a country like South Vietnam. The defoliation of one area merely forces the enemy to change his habits of movement, at most a logistical inconvenience. The use of defoliation for area denial has been more effective. An example can be found in the extensive defoliation of the Rung Sat Special Zone, south of Saigon. Here the defoliation program destroyed most of the mangrove forest in the area, effectively denying its use to large enemy units. The area, however, remains partially under the control of smaller enemy units.

Although defoliants have been used to clear roadsides, their effectiveness for this purpose has been disputed by many military commanders who have argued in favor of the use of Rome Plows and other methods. Evidence from enemy documents indicates that the primary concern of the Vietcong with respect to the defoliation program deals with the effects the defoliant might have had on personal health, not on strategic considerations.

Herbicides have also been used in the crop destruction program, considered by many to be the least effective U.S. program in the war. Long after food denial ceased to be a serious strategic objective the crop destruction program continued. The generally effective logistical structure of the Vietcong made efforts to control rice production and distribution ineffective.

Neither the crop destruction program nor the defoliation program was anything but a liability to pacification. Surveys conducted by local interview teams demonstrated that the use of defoliants was a matter of major concern to South Vietnamese peasants. A wide variety of real or imagined ills were generally attributed to their use. Accidents involving defoliants were not unusual and the bureaucratic procedure of the Vietnamese government in settling claims was not able to cope with the problems when they arose. In short, the use of herbicides in South Vietnam has carried with it several negative consequences which significantly outweigh their limited utility. This factor as much as any other led to the Administration's decision earlier this year to discontinue the crop destruction program and to phase out the defoliation program.

While the effectiveness of tear gas and herbicides in advancing U.S. objectives in South Vietnam may be open to further debate, it seems certain that neither chemical has played a major role in the war. Clearly the military need for the use of these agents in South Vietnam is not, in itself, sufficient justification for the U.S. position on the Geneva Protocol. This becomes increasingly true with each withdrawal of ground combat forces and the resulting decline in tear gas use.


The strength of the Geneva Protocol as an arms-control mechanism depends largely on the degree to which the parties to the Protocol agree on the nature of its prohibitions, and the extent to which the prohibitions can be clearly defined. In December 1969 a resolution in the United Nations General Assembly, designed to include both tear gas and herbicide use within the meaning of the Geneva Protocol, passed by an 80 to three margin with 36 abstentions. (Portugal joined the United States and Australia in voting against the resolution probably because of Portugal's use of herbicides for crop destruction and defoliation in Angola.) There can be little doubt as to where the majority of nations stand on this issue. If the United States ratifies the Protocol with the present understanding, the socialist nations, the majority of neutrals, and a sizable number of allies will not agree with the American position. However, if the United States took the initiative in interpreting the Protocol to include the prohibition of these chemical agents there is no doubt that a near unanimity of opinion could be obtained. This would greatly strengthen the Protocol.

In the interest of making international agreements enforceable, boundaries, prohibitions and limitations must be easily definable and conform as much as possible to natural dividing points. For this reason it has proven most desirable for international boundaries to be along rivers, mountain peaks, even clearly defined international geodesic lines, etc. When this principle is applied to the prohibition of gas in warfare, it dictates that a line should be drawn at a clearly definable point on the scale between "no gas" use and "total gas" use. It is argued by some proponents of the noninclusive Protocol interpretation that the distinction between the use of lethal gas and riot-control agents in warfare is a sufficiently clear distinction to allow all parties concerned to understand and abide by it.

This, however, is a dubious proposition. First, it must be understood that there is no agent which can be used in war with military effects which is nonlethal under all circumstances. Even the highly perfected tear gas, CS, used by the United States in South Vietnam, can be lethal where the victim is very old, very ill, or unable to escape the immediate area. While mortalities are very rare with the use of CS, there is no assurance that an enemy will necessarily use this form of tear gas. Therefore, some agreement would have to be reached on the exact degree of lethality which would be permitted. If, in fact, an agreement could be reached, it would be extremely difficult to determine whether a gas was causing three percent or five percent fatalities, or whether increased fatalities were due to stronger gas or increased quantitative use.

Another argument used by proponents of the U.S. interpretation is based on the "domestic-use" criterion; they argue that the Protocol should not prohibit for use in war chemical agents which are commonly used in time of peace. Domestically, tear gas is used for civil law enforcement and herbicides are used for agriculture. This argument has been widely used but it breaks down when we consider that the use of these chemicals in time of peace is quite different than it is during war. Nowhere in peacetime is tear gas used indirectly as a means of inflicting lethal casualties. Herbicides are not used for crop destruction or systematic forest defoliation in their normal domestic applications. In Vietnam, tear gas is delivered by mortars, artillery, helicopters, fixed-wing aircraft and mechanical blowers, none of which is used in domestic applications. In Vietnam, herbicides have been used to kill crops; in domestic use the purpose is to kill weeds in order to grow crops.

Problems associated with a less than comprehensive definition of gas restrictions can be seen by considering the difficulties of the U.S. Government in its attempt to enforce a tear gas policy in Vietnam. The public outcry over the use of tear gas in March 1965 led to a temporary ban on the use of such agents in South Vietnam. The weapons were not removed from the field, however, and it was only a short time before the use of gas began again. When the policy review on the matter was undertaken the same year, the State Department agreed that gas could be used in Vietnam if its use was confined to criteria set by Secretary Rusk. In a news conference on March 23, 1965, the Secretary stated: "These weapons will be used only in those situations involving riot control or in those situations analogous to riot control." Military expediency eroded the restrictions, however, and the attempt to limit the use of tear gas was a failure. The "riot-control" criterion was ineffective because it was ambiguous. Just as efforts to limit the use of tear gas at other than the "no tear gas" level broke down under the strain of combat, so, too, will the efforts to limit gas as a whole be severely strained under anything but the "no gas" interpretation. As Thomas Schelling notes in "The Strategy of Conflict": " 'Some gas' raises complicated questions of how much, where, under what circumstances: 'no gas' is simple and unambiguous . . . there is a simplicity to 'no gas' that makes it almost uniquely a focus for agreement."

While the potential for escalation of gas warfare is essentially qualitative, the potential for escalation of herbicide use is quantitative. In South Vietnam the United States has perfected the use of herbicides as anti-crop agents to a sufficiently high level that further qualitative efforts would not seem necessary. The techniques used in South Vietnam to destroy large quantities of crops can be used by other nations on almost any scale, including the systematic destruction of a nation's food production capability. Herbicides are used and manufactured for agricultural purposes in many countries of the world. It is well within the economic and technical capability of almost any nation to produce chemical herbicides as instruments of war, and to develop methods for delivering them. Using simple crop-dusting aircraft or converted military aircraft, a small nation can create enormous devastation in an opposing country at a fraction of the cost of other mass destruction techniques (except perhaps bacteriological warfare). Without benefit of "no first use" taboos such as those associated with the use of nuclear weapons, it is difficult to distinguish a level at which herbicidal escalation could be stopped or reversed.

The use of herbicides raises important environmental questions. Does the United States wish to be identified with a program which can so drastically affect environmental balances where it is used? Some of the forests of South Vietnam have been seriously damaged by the use of herbicides. Over large areas, the dead trees are quickly replaced by bamboo, making reforestation difficult. The herbicide-treated mangrove forests of the Rung Sat Special Zone and other areas have been completely destroyed. Many scientists have expressed concern over the possible effects of herbicides on humans. The principal military herbicide, Agent Orange, was banned from further use in 1970 due to preliminary evidence of the possibility that it produced birth defects after it had been used extensively in Vietnam. Of the two remaining agents used there today, neither is allowed for general agricultural use in the United States because of possible environmental and toxic effects. At a time when the United States is experiencing a growing environmental consciousness and can be expected to embark on a campaign for worldwide attention to environmental problems, the extension of a policy allowing systematic environmental destruction is both inconsistent and counterproductive.


Ethical arguments have been advanced on both sides of the Protocol issue. Proponents of the Administration's understanding have argued that tear gas is basically a humanitarian weapon which should not be prohibited for use in war. In most domestic cases tear gas is used by police because the offenses committed do not warrant the use of potentially lethal weapons. The Geneva Protocol by any interpretation would not limit the use of tear gas in normal police activities, even within a country at war. At the time of the policy debates on the tear gas issue, many felt that there were some unique humanitarian applications possible in war. It was argued that in cases where civilians were being used as a screen by the enemy, tear gas could incapacitate all parties involved, allowing time for separation and identification. In addition, it was felt that tear gas could be used to capture prisoners from tunnel complexes or caves. It was these humanitarian uses of tear gas which formed the most compelling arguments in the interagency debate in 1965, leading to Secretary Rusk's declaration that year.

The policies of 1965, however, have not proven realistic. Unfortunately, the use of tear gas in Vietnam has demonstrated conclusively that rather than being a humanitarian weapon of warfare, tear gas is most frequently used as a conventional military weapon to bring about indirect lethal effects. Since the Rusk statement in 1965 the use of tear gas in riot- control situations and in situations analogous to riot control has represented only a small fraction of the total use.

The use of herbicides to destroy crops also involves highly significant ethical considerations. In the course of investigations of the program in Saigon and in the provinces of Vietnam, I found that the program was having much more profound effects on civilian noncombatants than on the enemy. Evaluations sponsored by a number of official and unofficial agencies have all concluded that a very high percentage of all the food destroyed under the crop destruction program had been destined for civilian, not military, use. The program had its greatest effects on the enemy-controlled civilian populations of central and northern South Vietnam. In Vietnam the crop destruction program created widespread misery and many refugees.

It must be asked whether such a policy does not violate the nation's basic ethical standards. I believe it is a fair assumption that the national security is not only involved with physical security but also embraces the democratic and ethical concepts which form the basic raison d'être of the nation. It is important that the tactics used by the nation to preserve its security not come into conflict with the basic concepts which these tactics seek to secure. It is contrary to the broader meanings of the U.S. national purpose to perpetuate the use of tactics such as crop destruction in warfare.

It is important that the future of the Geneva Protocol not be solely dependent on the complex arguments relating to the immediate national interest. At this time, more so than at any other, the United States is in a position in which it can have a profound effect on the future of mankind. Historically, this era will be judged according to its ability to advance its technological capabilities for growth and development and to retard or restrict these same abilities for destruction. The Geneva Protocol of 1925 was a relatively small effort to achieve these objectives, but it was an important one. In this spirit the United States has recently taken the lead in efforts to prevent the proliferation of nuclear weapons, to propose negotiations which could lead to arms limitations, and to take a stand in opposition to the use of biological and lethal chemical weapons. It is in keeping with this historical trend that the present Administration must decide the fate of the Geneva Protocol. The alternatives facing the President are clear. If the current U.S. understanding is reversed or modified to include prohibitions against tear gas and herbicide use or if a concrete means can be presented to the Senate whereby the issue might be resolved among the parties, the Protocol would likely move to prompt Senate ratification. If not, there is little likelihood that the Protocol will be ratified during this session of the Congress. In making its decision the Administration must balance short-term military expediency against the long- term objective of prohibiting chemical and biological warfare.

In recognition of the dangerous consequences of eroding the meaning of the Protocol, and in recognition of the rapidly decreasing requirements for chemical herbicides and tear gas in South Vietnam, there is little question that the United States should now strive to obtain a unanimous interpretation of the Geneva Protocol to prohibit the use in war of all gases, bacteriological weapons and herbicides.

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