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January 01, 2003

Armed Conflict and Law in This Century

by Michael N. Schmitt

The attacks of September 11, together with more recent terrorist attacks in Bali, Moscow, and elsewhere, mark a sea change in the nature of conflict that has thrown the international legal community into a state of disquiet. Some assert existing laws’ adequacy, others suggest reinterpretation, and still others point to purported gaps requiring new law.

In fact, expressions of conflict had changed well before sensational acts of terrorism captured global attention. Technological advances have made twentieth century science fiction a reality. At the same time, and despite the purported “civilization” of humankind, hostilities are increasingly characterized by abuse of innocents. Perhaps most tragically, no one seems beyond the reach of twenty-first century violence. It is apropos, then, to examine where the law designed to govern armed conflict is heading.

Historically, law reacts to the past. For instance, the four Geneva Conventions followed closely on the heels of World War II. When they proved insufficient to meet the humanitarian requirements of conflicts such as Vietnam, Algeria, and Africa’s anti-colonial wars, international law again responded. Most notable were two 1977 Protocols Additional to the Geneva Conventions, the first codifying the rules regarding conduct of hostilities, such as distinction and proportionality; and the second expressly governing internal conflicts.

Despite hopes that the demise of the Cold War would presage an era of tranquility, the opposite occurred. On one hand, absence of superpower bipolarity meant that fear of nuclear escalation no longer restrained lower-level conflicts. On the other, collapse of multiethnic states like Yugoslavia and the Soviet Union violently unleashed pent-up hatred. The international community reacted with further codification of international law: the Chemical Weapons Convention, two Conventional Weapons Convention Protocols, the Ottawa Landmines Treaty, a Cultural Property Convention Protocol, a Protocol to the Convention on the Rights of the Child, and rules regarding the observance of humanitarian law during UN operations. The decade also witnessed creation of the first international war crimes tribunals since Nuremberg and Tokyo: the International Criminal Tribunals for the Former Yugoslavia (ICTY) and for Rwanda (ICTR).

What trends are likely to characterize conflict in this century, and what effect might they have on the legal regime? Five stand out:

Internal Strife

Noninternational (internal) armed conflict has surfaced as the leading form of organized violence. In 2001, all but one of the twenty major conflicts under way displayed some element of internal strife. Although weak states are especially vulnerable, none is immune (witness Chechnya). Unfortunately, norms governing internal conflict are underdeveloped (the core protections are Common Article 3 to the Geneva Conventions and Additional Protocol II). This is unsurprising, for states naturally resist limits on how they may deal with internal matters, particularly given the unlikelihood that their opponents will play by the rules.

Nevertheless, there is a growing sense that what occurs within a state’s borders should be the business of others. Operation Allied Force, NATO’s 1999 intervention in Yugoslavia, represents the most dramatic illustration. Consider also the global condemnation of the international community’s failure to intervene in Rwanda as hundreds of thousands were slaughtered in 1994, as well as international peace operations from the Balkans to East Timor. In the twenty-first century, external interference in other states’ internal affairs, even military intervention, increasingly will be deemed legitimate when states turn on their own citizens.

Additionally, the international community is finally willing to hold those involved in internal conflicts accountable for their actions. For instance, the ICTY exercises jurisdiction over crimes committed during the internal phases of the Balkan wars, the ICTR addresses abuses that occurred during a purely internal conflict, and International Criminal Court (ICC) jurisdiction extends to an extensive list of offenses during internal conflicts, even when committed by citizens of nonparty states. Also new are hybrid international-national courts like the Special Court for Sierra Leone. Cooperative ventures between the international community and the state that experienced the internal conflict, such tribunals balance legitimate state interests in controlling their own affairs with the community’s goal of limiting abuses. Most illustrative of this trend is the Milosevic trial, a prosecution for crimes against humanity and war crimes of a head of state who was turned over by his successors after being defeated in an open election.

Also apparent is a growing acceptance of codification in the field. In December 2001, for example, the Conventional Weapons Convention was amended to make all four of its operative protocols applicable during non-international armed conflict. Indeed, virtually all of the relevant instruments adopted in the last decade apply during internal conflict. Similarly, international tribunals are building a body of case law that supports application of international armed conflict law to internal hostilities. As the ICTY Appeals Chamber noted in 1995 during the Tadic proceedings:

[C]ustomary rules have developed to govern internal strife. These rules . . . cover such areas as protection of civilians from hostilities, in particular from indiscriminate attacks, protection of civilian objects, in particular cultural property, protection of all those who do not (or no longer) take active part in hostilities, as well as prohibition of means of warfare proscribed in international armed conflicts and ban of certain methods of conducting hostilities.


The events of September 11 presage terrorism on a scale heretofore unimagined, an era in which terrorists compete for dramatic effect. The transnational character of terrorism, as aptly illustrated by Al Qaeda, serves only to complicate matters.

Even in this formative period, the “war” on terrorism has forced reinterpretation of the law while drawing into question whether existing law even should be applied. Previously, for instance, the default legal response to terrorism was law enforcement. Self-defense, which permits robust military reaction, was understood in terms of attacks by other states. Henceforth, military options will increasingly be deemed legitimate exercises of the legal right of self-defense, whatever the source of attack.

Similarly, past sponsorship of terrorism seldom justified the use of military force against sponsor states, absent a showing that they directed groups conducting terrorist attacks. As the Taliban learned with the start of the U.S./U.K. bombing campaign, the international community will no longer tolerate even lesser forms of involvement. Nearly universal support for the strikes suggests dramatic evolution of this legal norm.

Terrorism also will affect application of the law governing how military operations are conducted. In much the same way that security concerns purportedly justify restrictions of civil liberties, states facing terrorists may justify noncompliance with international law by claiming their attackers ignore it—thereby turning the reciprocity that fosters compliance with the law on its head. Because state practice shapes international law, such tactics drive it in a negative direction and ignore that the law of armed conflict traditionally attempts to ensure a humane fight, not a fair one.

Some law simply does not work well in the context of terrorism, a point aptly illustrated by the controversy over the status of the Guantanamo detainees. Critics assert that some detainees, primarily Taliban fighters, qualify for prisoner of war (POW) status under the Third Geneva Convention. The Bush administration disagrees yet has not convened tribunals to determine status, as arguably required by Article 5 in cases of doubt. But do rules for POWs fit a war on terrorism? For example, the detaining power must release POWs at the conclusion of hostilities unless they are charged with a criminal offense; but this rule assumed return to a functioning state for reintegration into society. At least some released terrorists would simply disappear, only to strike again. Moreover, promptly trying terrorists may not be a viable option because the available evidence is weak compared with what can be gathered during classic military operations.


Technological advances are effecting a revolution in military affairs that has important legal consequences. For example, targets are vulnerable from great distances, with an accuracy measured in inches—precision that makes destruction possible using much less explosive force. The result is an improvement in compliance with the principle of distinction, which seeks to avoid incidental injury to civilians and collateral damage to civilian objectives.

Advances in information technology also foster compliance by rendering the battlespace ever more transparent. Enemy communications can be intercepted, computer nets monitored, and movements tracked around the clock, in almost any weather, all from technology that is beyond the enemy’s physical reach. Such transparency minimizes mistakes and enhances the capability to assess mission results, thereby diminishing the need to restrike a target and risk additional damage and incidental injury.

Technology even offers less destructive alternatives to conventional weapons. For instance, an air attack against Serbian radio-television headquarters during Operation Allied Force (OAF) caused civilian casualties and led to litigation in the European Court of Human Rights ( Bankovic). Today, the mission could be accomplished without physical destruction by targeting the facility’s computer network with a cyberattack.

Regrettably, technological advances also hinder the law of armed conflict, partly because only a few states can afford them. This impels the technological “have-nots” to consider tactics that place the civilian population at risk. For example, both Iraq and Yugoslavia used human shields in response to air strikes to which they could not respond in kind. Other examples include deliberately locating military objectives in civilian areas and feigning protected status, as has occurred in the Israeli-Palestinian conflict where ambulances are sometimes used to transport military equipment. Perhaps more perversely, technological disadvantage on the battlefield might cause a party to target civilians and civilian objects. The logic is simple: if it cannot hope to prevail on the battlefield, then it must seek other targets of value to its opponents. Because it is virtually impossible to protect an entire population, that population represents an appealing “soft target.” This is a logic not lost on terrorists.

Information technology’s ability to “blind” and confuse an enemy presents further problems. Computer network attack, to cite one example, can completely disrupt command, control, and targeting processes. Although this yields an enormous military advantage, it could diminish the enemy’s ability to distinguish between legitimate military targets and civilians and civilian objects.

Finally, technology has advanced to the point where modern conflict occurs virtually everywhere, including the virtual world. Sadly, this means there is no longer a natural separation of part of the population from the hostilities. At least in theory, there is no place to seek total sanctuary.

Compellance Strategies

Given the likelihood of any direct threat to their survival, the world’s most powerful states will fight only for limited purposes in this century; they will use force to compel others to engage in particular courses of conduct. “Compellance” strategies underpinned the efforts to force Saddam Hussein from Kuwait, to stop Milosevic’s murder of Kosovar Albanians, and to convince the Taliban (unsuccessfully) to put an end to Al Qaeda’s use of its territory. As the year draws to a close, the United States has threatened to use force to compel Iraq to comply with UN weapons inspections and destroy its weapons of mass destruction capabilities.

The internal logic of such efforts might actually encourage departures from recognized laws of armed conflict. First, the less important the objective, the less willing states will be to place their forces in harm’s way. A tactic that decreases risk to combatants often increases risk to others-and the less vital the ultimate objective, the less willing political and military leaders will be to risk their troops to achieve it. Yet risk to combatants is always present when conducting military operations in a way that ensures civilians the protection they are entitled to under the laws of armed conflict.

A second dynamic is subtler. Effective compellance strategies require altering the enemy’s cost-benefit calculations. Simply striking military targets may not do that, particularly if options are ruled out in advance (as with ground options during the campaign against Yugoslavia). This may lead to legally questionable targeting. For instance, in a widely reported interview, OAF’s commander suggested that one of his objectives was to deny Belgrade electricity so the population would pressure the government to comply with NATO demands. Although an electrical grid can be a legitimate target, it is not if it is struck because of its civilian nature. The same would be true of economic infrastructures.

America and the World

A widening divide exists between the United States and much of the world over issues related to law of armed conflict. To some extent, this is the product of U.S. refusal to opt into various treaty regimes, most significantly Additional Protocol I, the Ottawa Treaty, and the Rome Statute. America is increasingly viewed as a hegemonic hyper-power unwilling to play by the same rules as others. This attitude is exacerbated by controversies such as the Yugoslavia intervention, the treatment of the Guantanamo detainees, the search for immunity from ICC jurisdiction through bilateral agreement and Security Council exemptions, and threats to strike Iraq without Security Council authorization. The result is a common presumption that in gray-area incidents, U.S. action will be unlawful. (Many still believe U.S. forces intentionally struck the Chinese Embassy during the Belgrade bombing.)

This causes American attitudes to harden. It seems to many that those who do not have the capability or heart to engage in high-intensity, high-risk conflict seem to be pushing ever greater legal restrictions on those who do. Lest the divide widen, other states must start acknowledging the unique U.S. position and their own dependence on it when they send their forces into battle. They must give the United States its due when fashioning law governing hostilities.

Yet, because modern warfare is coalition based, it serves U.S. purposes to become more flexible to ensure it and its allies operate from the same rulebook. Opting into relevant legal regimes would inevitably place the United States in a leadership role and afford it profound influence on the course of the law. Most importantly, by doing this, the country would enjoy enhanced soft power. To the extent the United States is seen as a lawful actor, others will more readily follow or at least grant it the benefit of doubt in questionable cases. Unfortunately, this is not the case today.

Michael N. Schmitt

Michael N. Schmitt is a professor of law and director, Executive Program in International and Security Affairs, George Marshall European Center for Security Studies, Garmisch-Partenkirchen, Germany. This article reflects the author’s personal views.