What Kind of War? 11 September and Beyond

Journal article

Syse, Henrik & Gregory M. Reichberg (2001) What Kind of War? 11 September and Beyond, Security Dialogue 32 (4): 499–501.



Passenger aircraft loaded with jet fuel, commandeered by suicide bombers intent on destroying US landmarks of power and wealth, have produced the most spectacular peacetime attack since Pearl Harbor. While recent years have witnessed war-induced humanitarian catastrophes on a much larger scale, the events of 11 September nevertheless assume a chilling significance. They have raised the specter of a war between the United States (in association with its allies) and a nearly invisible adversary.

Some have questioned whether the US response to these attacks should rightly take the form of ‘war’. Preferring the language of law enforcement, they have argued that an international police effort is the appropriate response to these terrorist crimes. Concerted military action should be set aside in favor of economic and diplomatic efforts, intelligence work, policing, and other non-military measures.

This leads us to the question: What is war? Truth be told, there is no universally accepted, standard definition. ‘A regrettable expedient for asserting one’s rights by force within a state of nature, where no court of justice is available to judge with legal authority’, is how Immanuel Kant defined the term at the very end of the 18th century. 1 War, on this understanding, begins where law enforcement ends. This is a normative definition of war. It suggests that states may use military force to redress grave wrongs – prior attack chief among them – only in circumstances where legal remedies no longer exist.

The wanton destruction of 11 September was apparently mounted by civilians operating from Taliban-controlled Afghanistan. The Taliban government is responsible for the enforcement of law over these individuals. By allowing the perpetrators to operate within its territory, and by its unwillingness to cooperate in bringing them to justice, the Taliban regime has left the wronged state no choice but to assert its violated rights by force. Thus, we have a state of war.

However, while presumably complicit, the Taliban regime appears not to have been directly responsible for the attacks against the World Trade Center and the Pentagon. The credit has been laid at the feet of a clandestine network of internationally organized terrorists, led by Osama bin Laden. So the question is: Can or should war, properly speaking, be waged against that network? On the one hand, it seems that the law-enforcement model is more appropriate under these circumstances: bin Laden represents no state, and, furthermore, it would be unreasonable to accord him and his co-terrorists the special legal privileges due to prisoners of war; rather they should be tried in a civilian setting. However, if the retaliation is interpreted strictly as law enforcement, much more care must be taken to protect innocent parties from collateral harm. The threshold of acceptable casualties to bystanders is much lower in police action than in open war. Even while insisting that this is war, the USA should remember the many elements of law enforcement built into their actions and thus act with special care and discrimination in selecting and attacking targets.

Situated on an uneven ground between crime and war – having characteristics of each but falling squarely into neither – the terrorist attacks of 11 September merit a mixed response. In his groundbreaking Just and Unjust Wars, the philosopher Michael Walzer offered, under the heading of ‘peacetime reprisals’, a description which neatly sums up the dual aspects of the present case:

The legal handbooks divide their subject into ‘war’ and ‘peace,’ but much of history is a demi-monde that neither word adequately describes. It is to this demi-monde that reprisals most commonly pertain…. Now it is a feature of such periods that acts of force are not always acts of state in a simple sense. They are not the work of recognized officials and of soldiers acting on official orders, but (often) of guerrilla bands and terrorist organizations – tolerated, perhaps patronized by the officials, but not directly subject to their control. 2

War is situated in a zone beyond law enforcement. This is not to say that it is beyond law or morality. Having suffered an unprovoked, armed (though unconventional) attack, the United States, it is true, has no legal obligation to seek permission from the UN Security Council to mount a counter-offensive of its own. This reasoning is based on the idea of self-defense, which is indeed crucial here. Yet, in retaliating, the USA does have an obligation (legal and moral) to observe the applicable jus in bello rules of warfare – particularly those regarding discrimination and proportionality of means – the very same rules that its adversaries have so callously violated. And although the USA indeed has ‘just cause’ on its side (jus ad bellum), it must take care not to overreach that cause, using the 11 September attacks as a pretext to settle old scores with other enemies.

Morally and politically, we must say ‘no’ to terrorism, unequivocally condemning all groups, who – regardless of their motives, good or bad – employ this wicked tactic. Militarily, however, the United States now has warrant to punish only those guilty of the attacks of 11 September or those who show clear evidence of planning more of the same. Enlarging the military goal, so as to include all those ‘rogue states’ and other organized paramilitary forces (in the Palestinian territories, Lebanon, Indonesia, Northern Ireland, Sri Lanka, etc.) that contribute to terrorism in the general sense, has dubious ethical and legal credentials. Neither is it prudential, given the danger of protracted war on a large scale. Moreover, construing the war aim so very broadly will inevitably lead to disappointment and charges of hypocrisy on the part of states who imagined that the USA would actively join the struggle against their particular terrorist opponents.

The larger scourge of terrorism must rather be fought by other means, through the isolation of regimes that support terrorist organizations and by halting the flow of money to terrorists. This point, it should be noted, is also crucial in order to keep the armed retaliatory actions within the bounds of international law. Coming on the heels of the critical debate about NATO’s intervention in Kosovo, it is imperative that current actions conform to the jus ad bellum demands of international law. Undertaking military action beyond the limits of self-defense would indeed require a special mandate from the Security Council.

We would do well to remember that ‘terrorism’ is not a teaching or creed. One cannot go after it as if it were a clearly defined political entity. Terrorism – understood as the random murder of ordinary civilians with the aim of inciting disorder and fear – is a tactic that is primarily aimed at undermining the morale of the target group. 3 As such, it must be fought. But not all terrorism can be fought at once, and terrorism as such can never, alas, be eradicated. Our vulnerability in the face of terrorism is part of the human condition. This is no argument against violently attacking bin Laden and his network; it merely reminds us that total security from terrorism can never be gained.

The practitioners of terrorism seek to effect political change through the employment of force, yet by evading direct military confrontation. The essence of this strategy consists in what Liddel Hart termed the indirect approach, by which one group seeks to impose its will on another through non-conventional, or even non-military, means. 4 Pushing to the extreme a strategy often used in guerrilla campaigns, terrorists compensate for their lack of armed might by recourse to methods which prioritize psychological and political impact over victory on the battlefield. Spectacular and seemingly random attacks on civilian populations function much the same way as a leveraged buyout in business. Using few resources of their own, terrorists stand to reap large returns: a demoralized (hence weakened) enemy and, through the display of unexpected force in the service of a grand cause, the prospect of eager, new recruits.

The history of revolutionary wars, particularly in the 20th century – for example, in China, Algeria, and Vietnam – has shown the potency of the indirect approach and the futility of exclusively military forms of opposition. These lessons should not be lost on US leaders now, as they contemplate how best to assure the security of their citizens in the face of this grave terrorist threat. There is little doubt that ‘hard means’ must be directed against militants, such as bin Laden, who have openly espoused terrorist action against the USA and its citizens. Allowing them to operate with impunity, by favoring ‘softer methods’ more in tune with the spirit of nonviolence, will only embolden them the more. However, while the just war ethic allows for and even requires the application of this counterforce, it nevertheless counsels the appropriate restraint. Prudence likewise dictates the adoption of measures which will undermine the attraction of militant Islamic movements. Any show of force perceived to be excessive – especially if many civilian casualties result, as in the aftermath of the Gulf War – will drive still more young men and women into the militant camp.

Furthermore, while nonviolence, in our opinion, cannot take the place of military means, it still has an important role to play. The building of a ‘culture of peace’ through serious reconciliation processes, interreligious dialogue, and mutually trusted political arrangements is absolutely necessary. Indeed, the fight against the terrorism of 11 September must be waged on several fronts at once: military and economic, psychological, political, and moral. Against an adversary who operates from the territory of a very poor country, who is dependent upon relatively slim military resources, and whose chief asset is a renewable pool of highly committed (to the point of suicide!) members, the latter fronts will doubtless prove even more decisive than the former. Incapacitating bin Laden and his top lieutenants may turn out to be only the first step in a long road ahead. In the spirit of the just war tradition, the aim of this long journey must be unequivocal: a just and stable peace, not least in Afghanistan and the surrounding region. All the actions of war must be guided by that aim.

Gregory Reichberg & Henrik Syse

Senior Researchers
International Peace Research Institute, Oslo (PRIO)



1 Immanuel Kant, ‘Perpetual Peace: A Philosophical Sketch’, in Hans Reiss, ed., Kant: Political Writings, 2nd edn, trans. H.

  1. Nisbet (Cambridge: Cambridge University Press, 1991), pp. 93–130, on p. 96.

2 Michael Walzer, Just and Unjust Wars:A Moral Argument with Historical Illustrations (New York: Basic Books, 1977), p. 216.

3 We owe the formulation of this important point to Dan Smith, former director of PRIO.

4 For an illuminating discussion of the ‘indirect approach’, with application to 20th-century revolutionary warfare, see Général André Beaufre, La guerre révolutionnaire: Les formes nouvelles de la guerre [Revolutionary War: New Forms of War](Paris: Fayard, 1972).

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