European Affairs

NATO's Article 5: The Conditions for a Military and a Political Coalition     Print Email

On September 12, the day after the terrorist attack on the United States, NATO Secretary-General Lord George Robertson announced that, "If it is determined that this attack was directed from abroad against the United States, it shall be regarded as an action covered by Article 5 of the Washington Treaty," otherwise known as the North Atlantic Treaty.

This was the first time that Article 5 - the core element of the treaty and the basis for "collective defense" - had ever been invoked, after 40 years of Cold War and a decade of subsequent peace in which the allies had never needed to call upon this most fundamental strategic and political commitment.

In analyzing what this act means, it is important; to understand both what Article 5 is and what it is not. Four points about the text are especially important in the current circumstances:

  1. The application of Article 5 is limited geographically by Article 6 of the treaty to attacks against the territories of the member states and forces and ships at sea north of the Tropic of Cancer or in the Mediterranean.1 In 1949, U.S. Senator Arthur Vandenberg, whose Senate resolution was critical in ensuring that the treaty gained bipartisan American support, was particularly insistent that the treaty be regionally circumscribed. The wording was designed in major part to keep the United States from having to defend its allies' colonial possessions in Africa, Asia, and Latin America; although that point was turned against the United States at the time of the Vietnam War. But since the United States was attacked at home on September 11, Article 5 could apply. The treaty is silent, however, about where a military or other response can take place - in this case in Afghanistan, 7,000 miles from where the United States was attacked.
  2. The authority for taking action - including military action - is grounded in Article 51 of the UN Charter - the "right of individual or collective self-defense" - so that there is no need for the United States (or any other NATO power invoking Article 5) to go the UN Security Council for a resolution authorizing a military response.2 And since Article 5 links "an armed attack against one . . . [as] an attack against . . . all," NATO as a whole deems that it has the right to act without returning to the UN. This avoids the problem the Alliance had during the Kosovo Con§ict in 1999, when there was no UN Security Council resolution, without which some allies were reluctant to act.
  3. In terms of actual action, however, even though "an armed attack against one shall be considered an attack against them all," each ally is totally free to take "such action as it deems necessary" [emphasis added]. This could be "including the use of military force," but that - or any other action - is in no way required. Thus Article 5 does not automatically imply military action - another point on which the United States insisted when the treaty was being negotiated. As Secretary of State Dean Acheson said on March 18, 1949 (under pressure from Congress): "This [invocation of Article 5] does not mean that the United States would be automatically at war . . . The Congress alone has the power to declare war . . . [We would] be bound to take promptly the action which we deemed necessary to restore and maintain the security of the North Atlantic area . . . [but that] decision [would be] taken in accordance with our Constitutional procedures" [emphasis added]. Mr. Acheson went on to cite two factors in making such a judgment: the "gravity of the armed attack; and the action which we believed necessary to restore and maintain the security of the North Atlantic area." Thus, it is clear that, for NATO to act as a whole, there would have to be a further decision in the North Atlantic Council, as well as a separate, national agreement by each individual ally according to its own constitutional process.
  4. Article 5 presents a criterion for judging when any allied response has been effective. Action would be designed to "restore and maintain the security of the North Atlantic area." In the current situation, that could be very difficult to determine, especially since the September 11 attack did not involve Soviet forces pouring Westward across Europe, and, at least up to this point, no ally sees itself as being under a comparable threat to that facing the United States. Yet despite these significant limitations, Article 5 remains crucial, because of its gravity as a potent political commitment. As Mr. Acheson said in his March 1948 radio address to the nation: it would be a "question of faith and principle in carrying out treaties." Indeed, this was always the glue that held NATO together during the Cold War: the expectation that the United States would act upon "faith and principle" - as well as upon self-interest.

To ensure that there would be as few doubts in Europe as possible, much was done during the Cold War to ensure that the political commitment of Article 5 would, indeed, be carried out, including if necessary the use of the U.S. nuclear arsenal. To help make

that commitment believable, the United States stationed hundreds of thousands of troops and their families in Europe and, in the 1980s, deployed the so-called Euro-missiles, intermediate-range nuclear weapons.

Obviously, circumstances are different now. It is the United States, not Europe, which has been attacked; the attacker is assumed to be a non-state actor; and there is no critical, ongoing assault by massed armies: this is not World War III. Indeed, for most Europeans (though not all say it openly), this is not even "war," in the sense of their believing that they share an identical interest with the United States.

Why, therefore, did the Europeans endorse the invocation of Article 5 - even before they knew how many people from their own countries had also been killed, primarily in the World Trade Center? (People from about 80 nations were killed in the assaults on September 11: for the United Kingdom, for example, the losses were greater than from any single terrorist attack stemming from the con§ict in Northern Ireland).

First, there was the enormity of the attacks, the dramatic assault on civilians in a friendly country. No one in the West could be impervious to the shock and horror of this assault. It engaged the allied nations' collective, humane values.

Second, the United States was clearly hurting; and this mattered particularly because it is important to Europe in so many ways - economically, strategically, in terms of leadership, risk-sharing, and commitment - a point that came home to Europeans when they saw what the American nation was going through. Thus if the United States were damaged - even if mostly psychologically - in some way the Europeans would also be damaged, even beyond natural human sympathies and a recognition that this was a "crime against humanity."

Some if not all the allies felt a sense of obligation, in view of the fact the United States had done so much for European security from 1917 onward and even into the post-Cold War period, when the geostrategic risk to the United States from events in Europe had been so radically diminished - at least in the short- to medium-term - virtually to the vanishing point.

Third, there also rapidly developed in Europe a clear sense that, if the United States failed to respond effectively to these attacks, whatever within reason that would take, its credibility in the world would inevitably suffer. This could affect the Europeans' interests in the long term, since they still look to the United States to play a significant strategic role, not just in Europe but also elsewhere.

Fourth, the allies came quickly to the judgment that, quite apart from any Article 5 obligation, failure to stand with the United States at its moment of intense need could contribute to a lessening of the U.S. sense of commitment to Europe and even to a significant weakening, if not withering away, of NATO.

Fifth, most Europeans thus understood the political necessity of showing solidarity with the United States, even if Washington were to limit its requests for direct military support from allies to a select few - such as British engagement beginning on October 7, together with pledges of assistance by France, Germany, and Canada, as well as by non-NATO ally Australia.3 Indeed, the U.S. requirement for a coalition stems more from political than from military needs: the aim is to show that the United States is not "going it alone" in opposition to an Islamic person, group, or state. Washington adopted much the same approach in 1991, following the Iraqi invasion of Kuwait. Then, President George H.W. Bush put together a coalition of 31 states, including four Muslim countries, in order to give the lie to Saddam Hussein's contention that he was representing the "Arab street" against the "Zionists and imperialists."

Osama Bin Laden and his ilk obviously want the United States to overreact, and he would prefer that we do it alone, in order to advance his interests in radicalizing the region, gaining new converts, and undermining local regimes. The European allies, today, well understand the U.S. political need for coalition partners.

Finally, as the Europeans see U.S. determination, some of them worry that Washington may overreact militarily, cause substantial civilian casualties, or even use the crisis as an excuse to expand its goals - for example, to go beyond toppling the Taliban in Afghanistan, as part of seeking to capture and eliminate Osama Bin Laden and his network. Expanded U.S. goals could include the overthrow of Iraq's Saddam Hussein and perhaps even attacks on Iran or Syria.

With all these uncertainties about what the United States might do, European leaders clearly want to in§uence U.S. policy. President Jacques Chirac of France, British Prime Minister Tony Blair, German Foreign Minister Joschka Fischer, European Commission President Romano Prodi and other European leaders came rapidly to Washington to offer their support. In so doing, however, they also sought to gain standing to be able to counsel the President against overreaction. Judging from Mr. Bush's firm but temperate handling of the crisis through the time of writing, he seems to share much if not all of that perspective.

It is also striking that, in addition to the support voiced by the members of the North Atlantic Council, there have been various declarations by the European Union - in some ways even more important, because there is no Atlantic military framework within which such declarations are expected. These included the first-ever joint statement of all the heads of state and government of the EU member countries, plus the heads of all the EU institutions.

The European Council on September 21 also issued a remarkably strong statement. The Council said it was "totally supportive of the American people in the face of the deadly terrorist attacks. These attacks are an assault on our open, democratic, tolerant and multicultural societies:

"The EU will cooperate with the United States in bringing to justice and punishing the perpetrators, sponsors and accomplices of such barbaric acts. On the basis of Security Council Resolution 1368, a riposte by the United States is legitimate. The Member States of the Union are prepared to undertake such actions, each according to its means. The actions must be targeted and may also be directed against States abetting, supporting or harbouring terrorists."4

The EU also endorsed a wide range of counter-terrorist actions. Indeed, it is in the area of intelligence, police work, border controls, and actions against the terrorists' financial base that the United States most needs European help - not just in the short-term campaign to deal with Osama Bin Laden, but also in the long-term campaign against international terrorism in general.

This underscores the essential point that what is important is not the legalistic matter of the NATO Treaty's Article 5, but political solidarity and support. And this the allies have provided in abundance, while giving the United States wide latitude in terms of action.

So far, however, this applies only to "round one." Beyond eliminating Osama Bin Laden and as many of his associates as possible, avenging the September 11 attacks and demonstrating U.S. credibility, the Europeans - with some variations - may have different views about the further prosecution of a "war" against Middle East terrorism.

Unless one or more of the European countries is targeted in a significant way - and perhaps even then - they are likely to be cautious about U.S. actions that, in their view, could make matters worse by expanding the range of activity to other goals, thereby potentially spawning more support for terrorism or risking bringing down one or more pro-Western regional governments from within. Some allies will also want the United States to exploit potential opportunities, especially with Iran.

In general, Europeans will want the United States to do the following things:

  • apply a package of measures, emphasizing the non-military;
  • undertake active and uninterrupted efforts to resolve the Arab-Israeli con§ict, rather than being engaged only episodically, as many Europeans believe was the case for most of this year;
  • develop what Europeans would consider - but rarely define - as so-called "realistic" policies toward problems like Iraq and its effort to develop weapons of mass destruction, while not going to the point of possibly making matters worse; and not simply withdrawing politically and economically from the region, including Afghanistan after Osama bin Laden is taken care of - as the United States did after the Soviet Union left there in 1989. By contrast, most European leaders will want the United States to be careful about continuing to deploy troops permanently in sensitive regional areas, especially Saudi Arabia;
  • adopt a clear internationalist perspective on the world, in general, including firm support for international agreements, like the Kyoto Protocol on climate change, the Comprehensive Test Ban Treaty, the Anti-Ballistic Missile Treaty, and the Land Mine Treaty - even if some of these should properly be revised and improved;
  • consult closely with the allies on all activities affecting European interests - and show awareness that "multilateralism" has become the norm rather than "unilateralism;" and
  • avoid any suggestion of a division of labor within the Alliance, with the United States' acting primarily in the terrorism battle in the Middle East, while the Europeans take over responsibility in the Balkans (including Bosnia, Kosovo, and Macedonia). Such a shift of shared responsibility and potential risk could significantly undermine cohesion within the alliance. It will thus be important to see how, and for how long, Washington applies the allies' agreement to substitute their own forces in the Balkans ("backfilling") for those of the United States, if U.S. forces are withdrawn from the NATO area for the campaign against terrorism.

If these do, indeed, become the broad set of suggestions or requirements from various European countries, as an important element in continuing NATO engagement in the war on terrorism - beyond limited "coalitions of the able and willing" - it is not yet clear which of the guidelines the Bush Administration would be prepared to follow; although it can be argued that each of them is also in the U.S. self-interest, especially since September 11.

By the same token, it is not yet clear how far the Europeans, in general or as individual states, will also play their part in continuing to counter international terrorism, beyond non-military activities such as sharing intelligence and controlling financial §ows. But just as it is important for the United States to keep some military presence in the Balkans as a matter of NATO cohesion, it will be important for the other allies to understand that continuing to work with the United States in countering actions that have already led to one invocation of Article 5 can also become a major touchstone of NATO cohesion. The same can be true of EU efforts to help deal with problems within the Middle East and South Asian region, including the future of Afghanistan.

Thus, one further effect of the events on September 11 has been to move substantially forward the long-standing debate about the extent to which NATO should operate "outside of area," in this case not just beyond the formal areas defined by Articles 5 and 6 - e.g., the Balkans - but also beyond Europe. This issue remained unresolved as late as the NATO summit held in Washington in April 1999.

The summit meeting took place during the Kosovo con§ict, itself not completely accepted by all allies as a proper extension of NATO responsibility, although all agreed formally to make that determination. It thus seemed that for NATO the Kosovo con§ict was not "a bridge too far" - the sobriquet of the disastrous allied Arnhem Offensive in 1944 - but that it was at that point surely "the farthest bridge" of potential NATO military responsibility and action.

In its revised Strategic Concept, therefore, the Alliance referred to the possibility of common action beyond Europe only indirectly, in terms of potential threats, like terrorism, but not linked to "outside of area" territory.5 Since September 11, however, the issue has begun to be posed with great vigor: whether the NATO allies are prepared to act outside of area, when the threat emanates from there - and, indeed, when it can constitute an Article 5 situation by entailing an "armed attack."

Here, too, the issue of division of labor will be critical to NATO's future - with the Europeans' needing to accept their share of burdens beyond Europe, including counter-terrorism, just as the United States must accept its continuing share of day-to-day responsibility within Europe. At the same time, the European Union is also challenged, as part of its informal but critical strategic relationship with the United States, to see its Common Foreign and Security Policy (CFSP) - and, in some circumstances, perhaps, also its European Security and Defence Policy (ESDP) - stretched beyond Europe's confines, and to develop a partnership with NATO outside of area.

All this is part of the new strategic and political situation brought about by the events of September 11, with no real end in sight. It draws upon the political commitments contained in Article 5, but obviously goes far beyond, as the transatlantic security relationship, in its broadest definition - bilateral, NATO, CFSP/ESDP, and U.S.-EU - is reconfigured for the challenges of the 21st century.


This article was published in European Affairs: Volume number II, Issue number IV in the Fall of 2001.

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