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Report

NATO, the UN, and the Use of Force

Ivo H. Daalder

PRÉCIS

The debate surrounding NATO’s evolution from a collective defense alliance to an organization primarily concerned with managing crises centers around three questions:

1. Under what circumstances should NATO threaten use of force? The traditional criterion—self-defense against armed attack on any member’s home territory (Article 5 of the North Atlantic Treaty)—is too narrow. There is no doubt that NATO could embark on missions using force, if its members so desired, to confront crises or threats that do not directly affect allied territory but that may have implications for important national or humanitarian interests, (e.g., confronting arms proliferation or genocide)—though to what extent remains disputed within the alliance. The possibility for joint military action in a non-Article 5 context should not be conditioned on unanimous consent. An alliance that provides rapid and effective responses to crises in and outside allied territory, even if action is taken by a subset of allies, is preferable to one that conditions action on potentially unattainable unanimous support.

2. How far should NATO’s writ extend geographically? The American vision of a NATO acting globally is not widely shared by the European allies. For most of the Europeans, NATO’s fundamental purpose is to provide security in and for Europe. They have come to accept that NATO’s role extends into the Balkans—but this is about as far as it should go; for them, NATO remains a regional organization whose role is confined to the Euro-Atlantic region.

3. What is the legal basis for the threat or use of force by NATO in any of these situations? Two competing perspectives have emerged—a French perspective that gives the U.N. Security Council the primary role in authorizing NATO’s use of force; and a U.S. perspective that NATO has the right to use force whenever the interests of its members so
require. The NATO allies remain divided on whether Kosovo set a precedent for the future. Limiting NATO to actions that have been approved by the Security Council could subject the alliance to an effective veto by China or Russia. For this reason, NATO should not bind itself to a position that bars action in non-Article 5 contingencies if U.N. approval is not forthcoming. Still, the threat or use of force ought to have a legal basis sound enough to be acceptable both to the NATO public and to the vast majority of the international community—e.g., based on the U.N. Charter, the Helsinki Final Act, or the 1990 Charter of Paris.

Throughout much of its fifty year existence, the question of when and how the North Atlantic Treaty Organization could or would use force was not in dispute. As a military alliance formed to provide for the collective defense of its members, NATO sought to
deter and, if necessary, defend against an attack by the Soviet Union and its Warsaw Pact allies against the territory of one or more of its members. In case of such an attack, NATO’s military response against Warsaw Pact territory would have been both swift and automatic. The justification for this response would have come from the collective defense commitment enshrined in Article 5 of the North Atlantic Treaty, which is itself based on the right of individual and collective self-defense guaranteed by Article 51 of the United Nations Charter.

It was only in the 1990s, as first the major threat to NATO disappeared with the demise of the Soviet Union and then the Alliance’s purpose and missions began to shift, that the question of when and how to use force for purposes other than collective defense emerged. NATO members began to consider whether the Alliance ought to have a role in managing the multiple crises that were erupting in post-Soviet Europe as a result of the collapse of communist and Soviet imperial rule. Increasingly, the Alliance was seen not just as an instrument to defend allied territory against deliberate attack, but also as an organization that possessed the necessary military capacity to assist others in preventing, controlling, and mitigating the consequence of internal conflicts throughout Europe, particularly in the Balkans.

NATO’s evolution from a collective defense alliance to an organization primarily concerned with managing crises raised fundamental questions about its overarching purpose, the missions it should prepare for, and the role the threat and use of force should play in such missions. With regard to NATO’s future purpose, there is as yet no real agreement among the allies on what it should be. Some members continue to view NATO as primarily an alliance of collective defense whose main purpose is to provide a hedge against a militarily vengeful Russia that may emerge out of the political and economic chaos that marks present-day Russia. Others believe NATO ought to be an alliance of collective security whose main purpose is to promote the values of the Atlantic community of market democracies throughout Europe in an effort to spread the stability and security that derives from being part of the transatlantic security community. Yet others maintain that NATO can be an alliance of collective interests whose main purpose is to defend against threats to common, European and American, security interests no matter where these threats
come from.

On the eve of NATO’s 50th Anniversary summit, which will convene in Washington in late April, the allies have yet to resolve these competing visions of the Alliance’s future. These differences are reflected in the internal deliberations on the Alliance’s new
strategic concept that will be adopted at the Washington summit. The new strategic concept (the previous one of which has remained unchanged since the Soviet break-up) will guide Alliance planning on questions relating to the use of force and the development of capabilities for doing so into the next century. Three questions, in particular, remain in dispute. First, under what circumstances should NATO threaten or use force? Second, how far should NATO’s writ extend geographically? Third, what is the legal basis for the threat or use of force by NATO in any of these situations?

What follows is a brief overview of the main issues in contention regarding these critical questions. It ends with some suggestions on how the Alliance might resolve each of these questions as part of its revised strategic concept.

When should NATO Threaten or Use Force?

Author

Perhaps the least contentious question confronting the allies involves the circumstances under which NATO should consider threatening or using force. There is complete agreement among the allies in the case of a direct attack against one or more Alliance members. NATO members have the right—indeed, the obligation under Article 5 of the Washington treaty—to act forcefully to restore the status quo ante at the first possible opportunity. Of course, the allies recognize that with the disappearance of the Soviet Union and the collapse of its cold war Warsaw Pact adversaries, a direct assault on allied territory of the extent and gravity for which NATO was long prepared is virtually inconceivable.

Instead of a unified and large-scale threat to allied territory, the Alliance now must consider at least two types of challenges that could require a military response. First, although the threat of direct attack against Alliance territory as a whole has effectively
disappeared, a military attack against the territory of a single NATO country is still quite possible. This could take a variety of forms. For example, a country in North Africa, the Middle East, or beyond could launch ballistic missiles armed with conventional or more destructive weapons against a NATO capital or a military installation on allied territory. There could also be a terrorist attack by a state or non-state actor either in retaliation for some type of action by a NATO member or simply as a political statement of some kind. Or there could be a more conventional attack, which could result from either deliberate action or, more likely, the spill-over from a regional conflict.

In all these cases, NATO’s Article 5 commitment in principle would come into play, thus necessitating an Alliance response. In practice, however, the allies are unlikely to agree on the nature of either the challenge or the preferred response because their interests would be affected in different ways if any of these situations occurs. Whereas during the cold war forward defense in Germany was seen as the best way to defend not only Germany but also one’s own country against a Soviet invasion, a regional conflict or a single ballistic missile attack on one NATO country would have different implications for those allies not directly affected by the attack. The risks of direct military involvement would consequently differ, raising the likelihood that not all allies would respond similarly. That such differences can arise was demonstrated during the 1991 Gulf war when, faced with the possibility that Turkey might suffer Iraqi military retaliation, some senior German politicians argued, contrary to explicit NATO decisions, that Article 5 might not even apply. In other words, when the source and specific circumstances for an attack on a
NATO member are uncertain or contested, the interests of individual allies—and their willingness to respond militarily—are likely to differ as well.

Some situations in which allied territory is confronted with a direct armed attack may not be regarded by all allies as constituting the type of attack envisaged under Article 5. Two examples can help illustrate the point. First, if Iraq had responded to the four-day air campaign by the United States and Great Britain in December 1998 by launching a ballistic missile attack against Incirlik Air Force base in Turkey, some allies who objected to the British and U.S. action might have been unwilling to consider this an attack on a NATO member of the kind that would fall under Article 5. In a sense, the Iraqi retaliation was provoked by the U.S. and British air strikes and might, as such, be viewed as something less than a direct attack against a NATO country. Second, if a terrorist attack had occurred against a U.S. target on allied territory in response to the bombing of the Al Shifa chemical plant in Sudan (an action which few U.S. allies supported), it is doubtful that many, if any, allies would have viewed this as an Article 5 contingency. Indeed, neither the disco bombing in Berlin in 1986 nor the bombing of PanAm flight 103 over Lockerbie, Scotland in 1988, both of which were terrorist attacks against U.S. targets on or over allied territory, was viewed in such a manner. Differences over the nature and reason of an armed attack against allied territory are thus likely to remain sources of contention in determining whether any NATO response is warranted and, if so, what the appropriate response might be.

Another type of military challenge that may require a NATO military response involves crises or threats that do not directly affect allied territory, but that may have implications for important national or humanitarian interests. Bosnia and Kosovo represent two instances where the Alliance has made such a determination, deciding to use or threaten to use military force even though the Article 5 collective defense commitment was not directly at stake. In recent years, allied leaders and others have pointed to crisis
management and other non-Article 5 contingencies that could require NATO’s military involvement—to address a humanitarian emergency, counter proliferation, respond to terrorism, avoid or mitigate genocidal violence, or deter or defeat major aggression in
non-European regions. There is no doubt that NATO could embark on these types of missions if its members so desired. U.S. Secretary of State Madeleine Albright has explained, “founders of the Alliance were wise to allow us the flexibility to come together to meet common threats that could originate from beyond our immediate borders. . . . [W]hile the North Atlantic Treaty involves commitments to collective defense, it also allows us to come together to meet common threats that might originate from beyond the North Atlantic area.”

At the same time, it is clear that NATO is not required to act in these circumstances, and the question of whether NATO should engage in non-Article 5 missions and, if so, where and to what extent remain disputed within the Alliance. There are at least three different views on the matter. First, France, the new entrants, and, to some extent, Germany believe that NATO’s core mission is and must remain collective defense and the Alliance should consider engaging in non-Article 5 operations only to the extent that doing so does not detract from the allies’ ability to prepare for and, if necessary, meet the collective defense obligation. In addition, allies should eschew any non-Article 5 operation that risks escalating into an Article 5 commitment. Second, some of the southern allies and Canada maintain that in the absence of a significant military threat to allied territory, peace support and crisis management operations must become central functions of a transformed NATO. They argue that while the ability to conduct high-intensity combat operations must be retained (for the residual case of collective defense), the emphasis of NATO force planning and restructuring must be on strengthening the ability to conduct peace support missions in an era marked by extensive civilian-military cooperation. Finally, the United States and Great Britain argue that NATO must prepare for the full spectrum of
missions—ranging from peace support to regional collective defense operations within and beyond Europe. As NATO’s military authorities have recognized, the distinction between Article 5 and non-Article 5 missions is becoming operationally irrelevant. Moreover, since a non-Article 5 mission could spill over or escalate into an Article 5 contingency (as some feared in Bosnia and Kosovo), Alliance force planning must merge these two types of missions.

Given these different perspectives, what should the NATO allies do? Instead of limiting the circumstances under which NATO should threaten or use force to particular types of contingencies—be they regional collective defense or peace operations—the Alliance is best served if it emphasizes its willingness in principle to engage in the full spectrum of possible military missions. To focus exclusively on collective defense would prepare the Alliance for the least likely contingency, in effect marginalizing NATO as a Euro-Atlantic security institution. Similarly, insisting that NATO give priority to peace support and crisis management operations and placing a premium on preparing NATO forces and organizational structures for them, will likely erode the Alliance’s ability to conduct more robust combat missions—missions for which NATO as the only security organization in Europe or, indeed, the world is uniquely prepared.

The Atlantic Alliance must therefore prepare for the full range of possible military missions. In doing so, it nevertheless needs to set clear priorities for NATO planning. Without such prioritization the Alliance could quickly turn into an organization that is all things to all people in theory, while in practice being capable of conducting few, if any, missions. What, then, should be the Alliance’s focus? Where should lines be drawn, at least for planning purposes? While being prepared in principle to conduct a whole range of missions, NATO should concentrate its efforts and resources in three areas:

  • Crisis management operations within the Euro-Atlantic area, especially those that are designed to enforce norms, rules, and codes of conduct for relations within and between states in the region set out in the Helsinki Final Act and the 1990 Charter of Paris. The focus of NATO action should be both on situations involving particularly egregious violations of these standards of behavior and on providing the decisive military capabilities necessary to enforce compliance with these standards. This could include the deployment of forces in the crucial phases of a peace support operation, when (as in Bosnia and possibly Kosovo) implementation of an agreement’s provisions must be enforced and the general security environment stabilized.

  • Crisis management operations that could spill over or escalate into an Article 5 contingency. Relevant cases include conflicts near Alliance territory whose outcomes are crucial to member states’ security (e.g., conflicts involving Albania or Macedonia) and threats involving the use of weapons of mass destruction (WMD).

  • Regional collective defense missions in NATO’s southeastern (and perhaps its eastern) region, where the possibility of direct attack or the escalation of conflict, though not immediate, is not unrealistic. This would include contingency plans for regional collective defense of Turkey, Greece, Hungary, and possibly Poland and the Czech Republic.

In considering whether to conduct such missions, NATO countries should generally act on the basis of a formal decision by the North Atlantic Council. However, the possibility for joint military action in a non-Article 5 context should not be conditioned on unanimous consent, as some have argued. Doing so could require a prolonged effort to build an Alliance-wide consensus for action that could result in an unacceptable delay or even the failure to act. Such was the case in Kosovo in 1998. The search for a NATO consensus delayed a military response past the point when it could have been effective in mitigating the consequences of the violent Serb crackdown in Kosovo and laying a foundation for a plausible and sustainable political resolution to the conflict without a large international military presence to enforce it.

At a time when allied views on the nature of likely threats and the scope and extent of possible responses increasingly diverge, insisting on unanimity for joint action is as likely to result in an allied stalemate as in a decision to intervene. While always striving to achieve an Alliance consensus, the allies should agree that joint military action by some NATO allies may in certain circumstances be both possible and desirable even without a formal decision by the North Atlantic Council. Some may fear that this will undermine Alliance unity, while others may worry that certain allies will abstain from any participation and in effect become “free riders.” These concerns are real. But they must be weighed against the requirements for a flexible and adaptable instrument for joint military action at a time when allied interests vary more than ever. In the end, an Alliance that provides the basis for rapid and effective responses to crises in and outside allied territory, even if action is taken by a subset of allies, is preferable to one that conditions action on potentially unattainable unanimous support.

NATO’s Geographic Reach

Related to the differences among the NATO allies over the circumstances under which the allies should threaten or use force is the question of NATO’s geographic reach. In principle, there is nothing in the Washington treaty to prevent NATO from taking
military action wherever its members agree—in or out of Europe. Article 4 of the treaty stipulates that the members “will consult together whenever, in the opinion of any of them, the territorial integrity, political independence, or security of any of the Parties is
threatened.” This treaty article also provides the explicit basis for one of the four Alliance security tasks set forth in the Alliance’s Strategic Concept that was adopted by allied leaders in November 1991. That task was for NATO to serve “as a transatlantic
forum for Allied consultations on any issues that affect their vital interests, including possible developments posing risks for members’ security, and for appropriate coordination of their efforts in fields of common concern.”

In practice, however, there is no agreement on how far this commitment to consultation and the coordination of joint efforts extends geographically. On one side of the debate stands the United States, which, as a global power with global interests, argues that NATO should be the instrument of choice to deal with threats to the common interests of its members, wherever these threats arise. From this perspective, NATO’s fundamental purpose after the cold war should shift from defending common territory to defending the common interests of Alliance members. At the same time, U.S. officials stress that such an alliance of
collective interests would not become a “global NATO,” but rather a NATO that is globally active. In this era of globalization, it is argued, placing geographical limits on NATO’s reach and purpose would marginalize the Alliance in the foreign and security policy
of the United States and its major European allies, all of whom have interests that reach well beyond the geographical confines of the Euro-Atlantic region. As Secretary Albright explained at a meeting of the North Atlantic Council, “the United States and Europe will certainly face challenges beyond Europe’s shores. Our nations share global interests that require us to work together to the same degree of solidarity that we have long maintained on this continent.”

U.S. support for placing NATO in a global context rests on two arguments. First, the basic security threats confronting the United States and its NATO allies are located outside rather than within Europe. Europe today is at relative peace. For the first time in a
century, European stability is not threatened by a major power—be it a revisionist Germany or an expansionist Russia. Instead, Europe’s actual peace is today disturbed only by Serbia, which is led by a thug, whose actions cause large-scale human suffering but pose no fundamental or systemic threat to NATO countries or to European stability. At the same time, instability and threats to real, if not vital, interests do exist outside of Europe. These include WMD proliferation, terrorism, disruption of energy supplies, and challenges to the balance of power in critical regions like southwest and northeast Asia. Addressing these threats in concert would be in the interest of all NATO allies and therefore ought to guide NATO’s purpose. Second, if threats outside Europe pose the most immediate challenge to the shared interests of the NATO countries, the Alliance combines countries that are the most capable of dealing with these types of threats. It is therefore to the allies’ advantage to combine their considerable resources to defend against threats to their values and interests and to use NATO, the militarily most capable and best organized instrument, for that purpose. As Albright told her Alliance colleagues in December 1997, “when the world needs principled, purposeful leadership against aggression, proliferation, and terror, the nations represented in this room have to set other concerns aside and lead,
because few others can or will.”

The American vision of a NATO acting globally is not one widely shared by the European allies. For most European allies—including even those, like Britain and France, whose interests extend well beyond Europe—the Atlantic Alliance remains a quintessential European security organization, whose fundamental purpose is to provide security in and for Europe. The debate among them is not whether the Alliance should have a role beyond Europe, but rather how far beyond allied territory its role should extend. Most allies have come to accept that NATO’s role extends into the Balkans—as underscored by its leading role in Bosnia and Kosovo—but many believe that this is about as far as it should go.

In addition to perceiving NATO’s role in different ways, many allies are also quick to point out that their views of the interests, of the challenges and threats to those interests, and of the best way to respond to them often differ from those of the United States. This is particularly true in the Middle East, where U.S. and European perspectives on the nature of conflict and the preferred solutions have long diverged. It is also true regarding a threat that many regard as the preeminent post-cold war challenge to
NATO—the proliferation of weapons of mass destruction. Whereas Secretary Albright has argued that WMD proliferation constitutes as much of a unifying threat to the Alliance as the Soviet threat of yesteryear, most European allies neither perceive it as an immediate threat to Europe nor regard NATO as the primary instrument for effectively dealing with the WMD threat. International treaties and organizations, including the United Nations, as well as more ad-hoc supplier regimes are generally regarded as the preferred instruments for addressing proliferation. In contrast to the U.S. penchant for a policy of isolation and
confrontation, moreover, most Europeans believe that an emphasis on engagement is more likely to produce results. While the allies share an interest in halting proliferation, they neither see the threat in the same manner nor agree on NATO’s role in combating it. The same might be said of other challenges to common interests outside Europe.

In view of these differences, it is unlikely that the allies will agree to extend NATO’s reach beyond Europe any time soon. For most allies, NATO is a regional organization whose role is confined to the Euro-Atlantic region. This is consistent with the original
intent of the Alliance, which, as expressed in Article 10 of the Washington treaty, limited consideration of future membership to European states. Moreover, under the UN Charter, the Atlantic Alliance operates as a regional rather than a global organization. For these reasons, the allies should agree to generally limit NATO’s geographical reach—including the threat and use of force—to the Euro-Atlantic region. At the same time, they should do nothing that would deny those allies that so desire the ability to operate beyond this region if and when they believe it to be necessary. Indeed, one of the unique strengths of the Alliance is that it provides a solid foundation for joint military action by some or all allies in defense of their territory, values, and interests wherever such action they deem appropriate.

The Legal Basis of NATO’s Threat or Use of Force

Of the many issues relating to the threat and use of force by NATO that have divided the allies, none have been as contentious as the so-called mandate question, i.e., under what authority or on which legal basis can NATO threaten or use military force in other
than a collective defense contingency. At the outset of this debate, most allies believed that NATO should not act in this type of situation without an explicit mandate or authorization from the United Nations or the Organization for Security and Cooperation in
Europe. Allied leaders agreed as much at their 1994 Brussels Summit: “We reaffirm our offer to support, on a case by case basis in accordance with our own procedures, peacekeeping and other operations under the authority of the UN Security Council or the responsibility of the CSCE.” In recent years, however, there has been a growing division within the Alliance about the role and authority, if any, of the UN and other organizations in legitimizing or mandating the use of force by NATO. Two competing perspectives have emerged—a French perspective that gives the UN Security Council the primary role in authorizing NATO’s
use of force; and a U.S. perspective that essentially argues that NATO has the right to use force whenever the interests of its members so require.

The French perspective is based on the notion that the use force in international affairs, by a single state or group of states like NATO, is ultimately governed by the United Nations Charter. The UN Security Council is empowered by the Charter to determine the existence of any threat to or breach of peace (Article 39). At the same time, the Charter recognizes that states have the right to defend themselves individually and collectively (Article 51) and that regional arrangements or agencies can maintain peace and security within their region, provided they do so in a manner consistent with the purposes and principles of the UN (Article 52). The first purpose of the UN is to maintain international peace and security (Article 1) and one of its key principles requires members to refrain from “the threat or use of force against the territorial integrity or political independence of any state, or in any manner inconsistent with the purposes of the United Nations” (Article 2).

Given this legal foundation, it follows that NATO can resort to force in self-defense, either of a member state that is attacked or of a non-member state so long as the government of that state requests NATO’s assistance. The former situation falls squarely
within the collective defense commitment of the Washington treaty; the latter, as the case of Bosnia demonstrated, follows logically from the right of collective self-defense. At the same time, NATO cannot use force against another UN member state without its government’s consent if the action is not itself in defense of another UN member state unless the action is specifically authorized by the UN Security Council. That is the import of both Article 2 (which prohibits the use force against the territory or political independence of another state) and the proviso of Article 52 which limits action by regional arrangements such as NATO to those that are consistent with the purposes and principles of the UN. It follows from this reasoning that NATO can only use force in non-Article 5 contingencies either if it is invited to do so by the state involved or if it is explicitly authorized by the UN
Security Council. Accordingly, France (with support from some allies) has insisted that the revised NATO strategic concept should explicitly predicate the use of force by NATO in these circumstances on the Alliance receiving a mandate from the UN Security Council.

It should be understood that this legal perspective provides a convenient rationalization for limiting NATO’s role in Europe as much as possible to collective defense contingencies. That, after all, remains a major French objective. France views other institutions—the EU and OSCE in Europe, and the UN globally—as equally important in addressing post-cold war security challenges as NATO. Moreover, in contrast to NATO, in which France plays a distinctly minor role as a result of its refusal to participate in the Alliance’s integrated military structure, France is a leading member of the European Union and its power and influence in the OSCE is no less than that of any other state, including the United States. And in occupying one of five permanent member seats on the UN Security Council, Paris naturally has an interest in enhancing the role and authority of that body.

It is therefore not surprising that the United States does not share France’s perspective on this issue. Indeed, Washington prefers NATO precisely for the reasons Paris does not—the Alliance not only provides the United States with an institutional entrée into
Europe, but it is also an organization in which its influence is greater than that in any other international body. But there are more substantial reasons for U.S. opposition to the legalistic perspective France has championed. Critical among these is the implication
of the French position that NATO’s use of force in many non-Article 5 contingencies would be subject to a veto by two states (Russia and China) that do not share many of the values and interests that have long united the members of the Atlantic Alliance. Indeed, since both countries want to avoid setting the precedent that NATO or any other organization or groupings of states can intervene in the internal affairs of sovereign states, and if such intervention were to be conditioned on UN approval, either or both of the states is bound to use its veto in the Security Council to prevent forceful NATO action. As a result, the insistence on a UN mandate implies that the type of behavior Europe has witnessed in the Balkans during the last decade, including the widespread abuse of human rights and denial of fundamental freedoms, would go effectively unpunished or undeterred.

Given this practical reality, the United States favors leaving the decision on whether or not to use force up to the organization that would be responsible for undertaking such action—in this case to NATO. The Clinton Administration has argued that if nineteen
democracies deem the threat or use of force necessary to right a specific wrong, then that fact in and of itself provides sufficient justification and legitimacy for the contemplated action. No country would accept constraints on its freedom to act on behalf of its
own interests in the manner and at a time it judges best. It argues that the same should be true for any organization of democratic states that acts on the basis of consensus.

It was not until the crisis in Kosovo erupted in 1998 that the NATO allies were confronted with the practical implications of what had been up to that point a largely theoretical argument. By early fall, the Alliance was forced to consider whether to threaten significant air strikes against Serbia, a sovereign country in the middle of Europe engaged in indiscriminate violence against civilians in the province of Kosovo. France and others argued that NATO, as a defensive alliance, could not act in situations other than self-defense unless the action was explicitly authorized by the United Nations. Rejecting a NATO capable of issuing its own mandate as a “Holy Alliance,” French President Jacques Chirac argued that Paris “insists . . . on the need for a Security Council mandate for every NATO military intervention.” This view was shared by most NATO governments in Europe, including
Germany. Always hesitant about using military force, Bonn was particularly cautious in staking out a new position in the run-up to the October Kosovo decision given that elections in late September 1998 had brought to power a new, center-left government.
The United States, in contrast, argued that UN authorization would be welcome but not necessary for NATO to act. As the Pentagon’s spokesman argued in early October, “The U.S. view has always been that NATO has the right to act on its own—the right and the obligation to act on its own in matters of European security.”

Aside from these theoretical differences, the Alliance also faced a practical complication. Although the UN Security Council had unanimously voted in September 1998 to demand both a halt to the indiscriminate attacks against civilian populations in Kosovo and the withdrawal of Serb security forces engaged in attacks, a new resolution authorizing NATO to enforce compliance with these demands faced a near-certain Russian and/or Chinese veto. After an agonizing series of diplomatic discussions and last-minute reports of a possible diplomatic breakthrough, the North Atlantic Council voted on October 13, 1998, to activate NATO forces and authorize its supreme commander to commence air strikes following a ninety-six hour delay.

Faced with the likelihood that the UN Security Council would veto NATO action while a looming humanitarian catastrophe threatened tens of thousands of refugees stuck in the Kosovo mountains during winter, NATO decided to act. Allied nations offered a variety of legal rationales for their decision—including the fact that the UN Security Council had on two separate occasions identified the crisis inside Serbia as posing a “threat to international peace and security.” The situation thus warranted enforcement action under Chapter VII of the UN Charter. The Serbs had also clearly violated the Geneva Convention on
warfare. What proved decisive for many allies, however, was not that NATO under these circumstances could mandate itself to act, but rather the belief that the humanitarian crisis inside Kosovo could not be prevented without forceful action. As NATO’s Secretary General Javier Solana argued days prior to the decision, “NATO has to have the opportunity on a case by case basis to act, if necessary, under [its] own decision, always with an appropriate legal base, and always within the spirit of the [UN] charter. . . . There may be moments in which it is necessary to act for humanitarian reasons, when a UN Security Council resolution will not be necessary or will not be even appropriate because the UN charter does not contemplate humanitarian acts.” As for NATO’s right to act without explicit UN authorization, Solana argued that “it is a serious organization that takes a decision by consensus among serious countries with democratic governments,” implying this fact alone conferred sufficient legitimacy on the contemplated action.

Despite having taken this decision, the NATO allies remain divided over whether Kosovo set a precedent for the future. Whereas the United States suggested that Kosovo demonstrated that NATO could act without an explicit UN Security Council mandate, other governments steadfastly maintained that this decision should not be seen as creating a right for NATO to arrogate a mandate. Where does this leave the Alliance? In principle, NATO may embark on non-Article 5 missions without the consent of the government(s) involved only if its actions enjoy the authorization of the UN Security Council. In practice, however, limiting
NATO to those actions that have been approved by the Security Council could subject the Alliance to an effective veto by China or Russia. For this reason, NATO should not bind itself to a position that bars action in non-Article 5 contingencies if UN approval
is not forthcoming. At the same time, although consensus among nineteen democratic states does provide a certain degree of legitimacy, the notion that NATO may arrogate the legal right to intervene in conflicts against the will of the government concerned is unsustainable. NATO cannot for long act like the Athenians who, in confronting the Melians during the Peloponnesian War, justified their action by asserting that “the strong do what they will, the weak do what they must.” While Melos was conquered, Thucydides has reminded us that Athenian hubris proved to be that power’s subsequent undoing. Of course, in view of the lack of consensus within NATO on when and how to intervene, the point may well be moot. Nevertheless, the use or threat of force ought to have a legal basis sound enough to be acceptable both to NATO publics and to the vast majority of the international community.

The Kosovo model of constructive ambiguity goes a long way toward filling the gap between requiring an express UN mandate on the one hand and NATO’s self-mandating on the other. This approach recognizes that the authority to act in difficult cases may not be viewed in precisely the same way by every NATO member state, some of which may embrace a right of humanitarian intervention in response to gross violations of human rights or genocide, while others may require at least some relevant Security Council resolution short of express authorization (e.g., a finding that the conflict in question threatens international peace and security). Constructive ambiguity can thus allow agreed action to occur at a time when legal norms regarding the use of force in situations other than self-defense are still evolving.

Although this approach may be politically expedient (and close to what NATO is likely to favor), it does not provide a sound foundation for planning or public diplomacy, if only because the formula’s very ambiguity rules very little in or out. This raises the question whether an agreed legal foundation can be found to provide an appropriate basis for the possible use of force by NATO in non-Article 5 contingencies. One answer is that the provisions of three key documents to which all NATO members are signatories could furnish such a basis. These are, first, the UN Charter, and particularly its primary purpose of maintaining international peace and security; second, the Helsinki Final Act, which underscores that respect for “human rights and fundamental freedoms . . . is an essential factor for the peace, justice, and well-being necessary to ensure the development of friendly relations and cooperation” among the signatory states (i.e., all OSCE members); and, finally, the 1990 Charter of Paris for a New Europe (also signed by all OSCE states), which further elevated human rights and fundamental freedoms and declared that their
“observance and full exercise are the foundations of freedom, justice, and peace.”

The Charter of Paris, in particular, could supply the foundation on which to build a solid legal basis for NATO action in non-Article 5 situations, including the threat or use of military force, at least in cases involving genocide and or other serious violations of
human rights. To be sure, this document, like the UN Charter and the Helsinki Final Act, affirms the principle of non-use of force against the territorial integrity and political independence of any state. But by emphasizing the primacy of human rights and affirming that “full respect for these precepts is the bedrock on which we will seek to construct the new Europe,” the Charter provides a foundation for military action in response to gross violations of human rights or the denial of fundamental freedoms, at least within Europe. Of course, determining whether such an extreme violation has occurred will always remain subject to differing interpretations among the allies. Nevertheless, if and when a NATO of at least nineteen democratic states can agree that such a violation has occurred and forceful action is deemed necessary, then such action could be judged to be legitimate. In short, an agreed legal basis along these lines would enable the Alliance to take such action as it sees fit in cases of threats to or breaches of international peace and security involving gross violations of the human rights principles that are articulated in the UN Charter and the Helsinki Final Act, and further refined in the Charter of Paris.

Conclusions

As the members of the most successful military alliance in history prepare to celebrate NATO’s 50th Anniversary, they are confronted with a notable paradox. On the one hand, the Atlantic Alliance has weathered the end of the cold war and emerged as the premier security organization in Europe. In contrast to the EU, OSCE, and even the United Nations, NATO is today viewed by members and non-members alike as Europe’s “go-to” organization in those cases where the threat or use of force is deemed appropriate. On the other hand, the Alliance’s fundamental purpose in the new Europe is contested. Its members—old and new
alike—have yet to fully agree on what a military organization born and raised in response to an overwhelming military threat emanating from the Soviet Union ought to do now that this threat has disappeared. Nowhere is this difference of purpose more apparent than in regard to the issue of when and how NATO should use force.

As the discussion above has made clear, allied differences over the circumstances under which NATO should threaten or use force, how far its writ should extend geographically, and what the legal basis for NATO’s threatening or using force in any of these situations ought to be remain profound. At the same time, some of these differences are more apparent than real, often a matter of style rather than substance. And in each case, reasonable compromises that are consistent with most points of view can be developed. Their acceptance by the NATO allies depends, however, on a willingness to abandon, at least for now, both highly restrictive and highly ambitious views of NATO’s overriding purpose. If NATO’s purpose is solely to provide for the collective defense of its members, then many of the issues regarding the use of force by the Alliance will have been settled, but only by
making the organization virtually irrelevant to the main security challenges of the day. Similarly, if NATO’s purpose is to defend challenges to a broad set of European and American interests on a global basis, then differences among the allies on the interests
involved, the threats to those interests, and the nature of the appropriate response will likely paralyze the Alliance and ensure that inaction becomes the rule rather than the exception.

Instead, a middle ground must and most likely will be found. While NATO’s core function must be to provide not only collective defense but also a foundation for joint military action whenever concerned allies so desire, its central purpose should be to extend
the security and stability its members have long enjoyed to other countries throughout the Euro-Atlantic area. The allies can achieve this purpose in part by holding open the door to Alliance membership to any European states that both desires to join and has made the necessary political, economic, and military reforms. But it also means that the Alliance must become a key instrument in promoting the values and interests that set Europe apart from other regions in the world—including support for democracy and the protection of human rights and fundamental freedoms. NATO brings to this task the unquestioned ability to
deploy and use overwhelming military force. The threat of its use is often sufficient to ensure that states in Europe respect the norms, values, and codes of conduct governing their behavior to their citizens and neighbors alike. Sometimes, however, more than
threats are required, and NATO has demonstrated in the Balkans that it is willing to use force in order to promote security and stability throughout the region.

If NATO’s central purpose becomes promoting security and stability throughout the Euro-Atlantic area, then it will be possible for the allies to agree on when and how NATO should threaten or use force. Specifically, the Alliance could increasingly view the threat or use of force not only in terms of providing a credible deterrent and defense of allied territory, but also as a critical tool for helping to enforce the norms, values, and code of conduct that govern behavior within and between states in the Euro-Atlantic region. This would include the kind of operations NATO has conducted in the Balkans during the past years—including threatening force to protect civilian populations in Bosnia, deploying troops to help enforce peace agreements in Bosnia (and, soon, in Kosovo), and conducting air strikes to force recalcitrant parties to seek a peaceful solution to conflict as happened in Bosnia and may still happen in Kosovo.

Second, as for NATO’s geographical reach, although the Alliance should provide a solid foundation for joint military action by allies when and wherever they deem such action to be necessary, the emphasis for NATO’s forceful action should be focused on dealing with situations in rather than beyond Europe. The Alliance is not today—and is unlikely to become any time soon—an appropriate instrument for using force outside of Europe. Its focus and planning horizon should therefore remain on Europe.

Finally, whenever possible, NATO should threaten or use force with the full backing of the international community, as expressed by the UN Security Council. It did so in Bosnia, receiving UN authorization not only prior to the conclusion of the Dayton Peace Accords, and also when it deployed some 60,000 troops to assist in the Accord’s implementation. The draft interim agreement for Kosovo stipulates that the UN be invited to endorse a NATO-led peace operation to support implementation of such an agreement. At the same time, the Alliance cannot be held hostage to the whims and fortunes of non-NATO members, including
potential Russian or Chinese vetoes. As an alliance of democratic states acting on the basis of consensus, NATO must maintain the possibility of acting without specific UN authorization. Even then, the allies should strive to act only on the basis of appropriate
legal instruments, including the UN Charter and, for actions in Europe, the Helsinki Final Act and the Charter of Paris for a New Europe. The latter, in particular, provides a sound and solid legal foundation for threatening or using force in cases where human rights or fundamental freedoms are being denied.

In sum, NATO enters the next century as the only major security organization that is capable of wielding significant military force in Europe. It should do so only in support of efforts to extend security and stability throughout Euro-Atlantic region. And the
Alliance can do so without recourse to non-European institutions so long as force is employed in support of sound purposes and principles to which all states in Europe subscribe.

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