WOULD IT BE "murder," under accepted standards of international law, to kill Saddam Hussein? Or could it under certain circumstances be a morally preferable and legal alternative to more conventional means of responding to armed international aggression?

The recent suggestion by Michael J. Dugan, then Air Force chief of staff, that the United States might seek to "decapitate" Iraqi leadership by targeting Saddam Hussein, his family and even his mistress, caused a great deal of understandable outrage in this country and abroad, and has refocused attention on the permissibility of "assassination" as an instrument of U.S. policy.

It may or may not prove appropriate to target Saddam Hussein personally should a resort to armed force prove necessary. But neither "law" nor "morality" should conclusively prohibit such a decision from being made on the merits.

As a nation we believe in the rule of law, and humanitarian constraints designed to mitigate the horrors of battle play a valuable role in the modern international system. Further, as a matter of national policy, both prudential and ethical considerations mandate that killing foreign leaders should not be an acceptable response to even the most severe political or economic grievance. Not only is "assassination" prohibited by Executive Order 12333, but the intentional targeting of non-combatants is a violation of the 1949 Geneva Conventions -- which are part of the supreme law of the land.

It is important, however, to distinguish between "assassination" and the intentional killing of an individual under circumstances in which the act may be morally and legally justifiable. The real issue is not the term used to describe the act -- characterizing the murder of a foreign political figure an act of "neutralization," as some have done, contributes nothing to its legal or moral justification. The issue is rather one of distinguishing between acceptable and unacceptable uses of force. The indiscriminate expansion of "assassination" -- commonly defined as a form of political murder -- to encompass every intentional killing of a foreign official risks confusing some highly complex and quite distinct legal and moral issues.

Murder ought never to be an element of American foreign policy. But all "killing" is not "murder," and both international and municipal legal systems recognize limited circumstances in which lethal force may justifiably be used. Under both systems, for example, the taking of human life may be sanctioned as a "lesser evil" when absolutely necessary to resist life-threatening armed aggression.

In its essence, the moral dilemma is a choice between competing evils: whether it should be lawful, in a situation in which resort to armed force is otherwise clearly permissible, to target a foreign head of state who is engaged in flagrant violations of international law, if peaceful avenues of redress have been exhausted and the alternative is a use of massive force likely to produce tens of thousands of military and civilian casualties. Historically, there has been an on-going debate about the moral and legal permissibility of intentionally killing a foreign head of state who had initiated an aggressive war. In the eyes of the law, of course, it didn't matter much who "initiated" the war, since in the past such conduct was viewed as a prerogative of kings.

For obvious reasons, kings and their agents sought to prohibit or place limits on the "assassination" of national leaders -- outlawing at minimum assassination by such "treachery" as the use of poison. But these rules arose in a context in which the initiation of war was fully legal. Even then, they were challenged by people like Sir Thomas More, who argued that treacherous assassinations of those "responsible for the wars" were justified if the destruction of the innocent would thus be prevented.

Such central figures in the development of modern international law as Grotius and Byenkershoek contended that the law permitted assassination in wartime. Developments in the modern era have arguably strengthened a strictly limited variation of this claim: Launching an aggressive war is today recognized as a matter of international law as among the greatest crimes against mankind.

Despite a general protection of sovereign immunity, heads of state may lawfully be held accountable for certain wrongful conduct. For the U.N. Security Council to authorize a necessary use of force against Saddam Hussein would, in many respects, be comparable to permitting the police to intentionally take the life of a bank robber who was systematically murdering hostages.

A few principles of international law are relevant to the current situation. First of all, Article 2(4) of the U.N. Charter prohibits "the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations." Article 51 of the Charter sets forth a complementary principle that, in the event of armed aggression, states have an "inherent right of individual or collective self-defense" in the absence of effective Security Council action. Under Article 42, the Security Council may also authorize the use of armed force in response to a threat to or breach of the peace.

A use of force in self-defense or collective self-defense must meet two requirements to be lawful. It must be "necessary," which means that peaceful attempts at bringing the aggression to an end are ineffective. In addition, to be lawful, defensive force must be "proportional," which is to say that international law permits only that level of coercion necessary to achieve the permitted goals (in the present crisis: the termination of Iraqi aggression against Kuwait; the restoration of the status quo ante and the release of foreign hostages).

In addition, the so-called "Nuremberg Principles" recognize that the planning or waging of a war of aggression is a crime against all states for which even heads of state may be held personally liable. Article six of the 1945 Nuremberg Charter identified the "planning, preparation, initiation or waging of a war of aggression, or a war in violation of international treaties, agreements or assurances, or participation in a common plan or conspiracy for the accomplishment of any of the foregoing," as "crimes against peace" for which there shall be individual responsibility. On motion of the United States and with the concurrence of Iraq, this principle was unanimously affirmed as reflecting customary international law by the U.N. General Assembly in 1946.

Iraq's invasion of Kuwait has been condemned as a breach of international peace and security by Security Council Resolution 660, and there can be little doubt that the council has authority to initiate a war-crimes trial which could produce a sentence of death for Saddam Hussein and other Iraqi leaders.

Perhaps I was overly influenced by my experiences in Vietnam, but I returned from that tragic conflict with the dual convictions that armed aggression is a horrible wrong and that the lives of soldiers, too, have value. There are, to put it in moral terms, such things as "innocent soldiers" in the modern world -- and not all of them are in American uniforms. To the extent possible, the Security Council ought to seek an outcome to the current crisis which places appropriate value on the lives of the soldiers and innocent civilians on both sides.

Even if one rejects my characterization of many soldiers on both sides of the battle as being "innocent," history establishes that armed conflicts inevitably claim the lives of large numbers of non-combatants. To argue as a matter of either legal or moral principle that, above all and without possible exception, the life of a head of state guilty of armed aggression must be safeguarded -- to give him the protected status of a Red Cross or medical worker -- is to argue that it is better to kill 10,000 innocent individuals than to take the life of one guilty man. This is not, in my view, a self-evident legal or moral truth.

A fundamental reason underlying the Nuremberg Principles is that aggressors ought to be held accountable for their crimes against mankind -- if for no other reason than to serve as a deterrent to future potential aggressors. The "proportionality" doctrine of international law supports a conclusion that it is wrong to allow the slaughter of 10,000 relatively innocent soldiers and civilians if the underlying aggression can be brought to an end by the elimination of one guilty individual.

Ideally, of course, the most elementary principles of justice require that such "guilt" be determined through judicial process in which all rights of the accused are protected. But the basic facts of the situation do not appear to be in serious dispute. It is difficult to argue that thousands of innocent lives must be sacrificed to safeguard the procedural interests of one obvious criminal.

There are certainly numerous prudential and political considerations which might mitigate against targeting Saddam Hussein: A leaderless Iraq or successor government, for example, might become even more radical and obstinate to international pressure. Moreover, even appearing to let the "assassination" genie out of the bottle might encourage attacks on political leaders for other reasons. Policymakers may well conclude that large-scale military casualties are preferable to a more discriminating response focused on Saddam Hussein and others who bear moral responsibility for the current crisis.

In the aftermath of Dugan's unfortunate remarks -- and there is no more legal or moral justification for intentionally targeting Saddam's family and mistress (a flagrant and unjustifiable violation of international law) than there is for requiring the innocent people of Iraq to pay the primary cost for his acts of aggression -- some members of Congress will likely be tempted to "codify" a vague prohibition against "assassination" into permanent American law. Before doing so, they ought to carefully consider whether the absolute protection of Saddam Hussein, Adolf Hitler or other international criminals in the years ahead is really worth the lives of the thousands of their constituents who might be placed at risk in a more conventional response to aggression, if Congress were to leave that as the only "legal" alternative.

Robert Turner teaches international law at the University of Virginia and is chairman of the American Bar Association's standing committe on law and national security. The views expressed are his own.