An atrocity took place on a scale and of a level of barbarity that it appalled the entire world and, from the NATO perspective, led to a fundamental change in the way in which the Alliance operated and the kind of task it dealt with. The atrocity was the Srebrenica massacre of July 1995.

The groundwork for NATO's expanded role in Bosnia and Herzegovina had been prepared in the previous years in internal Alliance documents as well as agreements with the United Nations and the Conference on Security and Cooperation in Europe. However, before the Srebrenica massacre, Allies had remained reluctant to take the logical next step and launch the kind of intervention that might end the war.

In the wake of Srebrenica, in which possibly as many as 8,000 Bosnian Muslim men and boys were summarily executed by Bosnian Serb forces, international attitudes against the Bosnian Serbs hardened. Within two months of the massacre, NATO had carried out its first air campaign, leading to the signing of a peace agreement to end more than three-and-a-half years of fighting. By December of that same year, NATO was leading a peacekeeping mission in Bosnia and Herzegovina and providing the security for a peace process to take root.

The terrorist attacks of 11 September 2001 have had an even greater impact on Alliance strategic thinking than the Srebrenica massacre. A day after hijackers flew commercial airliners into the World Trade Center in New York and the Pentagon in Washington, the Allies responded by invoking Article 5 of the Washington Treaty for the first time in the Alliance's history. And by agreeing that a terrorist attack by a non-state actor should trigger NATO's collective self-defence obligation, the Alliance had, in effect, mandated itself to make combating terrorism an enduring NATO mission.

Since then, NATO's political and military authorities have put in place the building blocks for a comprehensive Alliance approach to terrorism, which could have similar, long-term implications for the way in which NATO operates. On the political side, the North Atlantic Council has decided that NATO should be ready to help deter, defend, disrupt and protect against terrorist attacks directed from abroad, as and where required. It should be ready to help national authorities cope with the aftermath of attacks. And, on a case-by-case basis, the Alliance should consider providing its assets and capabilities to support operations, including those against terrorism, undertaken by or in cooperation with the European Union or other international organisations or coalitions involving Allies. On the military side, NATO now has a military concept for defence against terrorism for which the Alliance's military authorities are now developing a concept of operations to put it into effect.

Such measures have clearly been in the Alliance's best, long-term interest as increasingly its relevance is measured by its contribution to the war against terrorism. Indeed, had the Alliance been unable or unwilling to contribute to addressing the challenges posed by terrorism and weapons of mass destruction, it would have risked detaching itself from the US security agenda thereby ceasing to be an effective organisation.

To be fair, what the Alliance was doing before 9/11 — rebuilding failed states in the former Yugoslavia, forging partnerships with Russia, other former adversaries in the East and countries in the wider Mediterranean region and expanding Europe's zone of stability by bringing more countries into the Alliance — was extremely relevant for Euro-Atlantic security and remains equally relevant today.

Moreover, even prior to 9/11, the Alliance was beginning to face up to the challenge of terrorism. The Strategic Concept that NATO leaders adopted at their Washington Summit in 1999 included the following reference: "Alliance security must also take account of the global context. Alliance security interests can be affected by other risks of a wider nature, including acts of terrorism, sabotage and organised crime, and by the disruption of the flow of vital resources..."

However, despite this recognition, the Alliance gave terrorism relatively little collective attention. This was largely because there was no consensus on NATO's role in what were seen by most Allies as internal security problems. As a result, there was little or no sustained discussion of the nature of terrorism, of its sources, or its implications for Alliance concepts, policies, structures or capabilities.

But 9/11 changed terrorism from what was essentially a domestic, law-enforcement concern, into an international security problem that, if it is to be adequately addressed, requires a broad spectrum of political, economic, and law-enforcement measures, as well as military engagement.

The first step in NATO's response was the invocation of Article 5. But having taken this unprecedented action, the Allies' initial contribution to the US-led campaign against al Qaida and the Taliban in Afghanistan was modest [for details of early NATO support, see article Aiding America in the winter 2001 issue of NATO Review]. In the intervening period, however, Allies have played an increasingly significant role. Indeed, 14 NATO countries deployed forces to Afghanistan.

At their Reykjavik meeting in May last year, NATO foreign ministers agreed that: "To carry out the full range of its missions, NATO must be able to field forces that can move quickly to wherever they are needed, sustain operations over distance and time, and achieve their objectives." Since then, NATO has begun to provide support to those countries, currently Germany and the Netherlands, which are running the International Security Assistance Force in Afghanistan. And at the Prague Summit, NATO leaders endorsed a lengthy package of measures and initiatives, virtually all of which can be considered as designed to combat terrorism.

NATO's new capabilities initiative, the Prague Capabilities Commitment (PCC), is designed to improve, among other things, the Alliance's terrorism-related capabilities and in general to ensure that European militaries are equipped to move faster and further afield, to apply military force more effectively and to sustain themselves in combat. It includes the following eight fields: chemical, biological, radiological and nuclear defence; intelligence, surveillance and target acquisition; air-to-ground surveillance; command, control and communications; combat effectiveness, including precision-guided munitions and suppression of enemy air defences; strategic air and sea lift; air-to-air refuelling; and deployable combat support and combat service support units.

Once implemented, the PCC should at least quadruple the number of large transport aircraft in Europe, from 4 to 16 and possibly more. It will also significantly increase air-to-air refuelling capacity among NATO's European members by, among other initiatives, establishing a pool of 10 to 15 refuelling aircraft. And it will increase NATO's stock of non-US, air-delivered, precision-guided munitions by 40 per cent by 2007.

Another Prague initiative, the NATO Response Force, which should have an initial operating capability by October 2004, is designed to give the Alliance a new capability to respond quickly to an emergency, to go wherever required, and to hit hard. And NATO's Military Command Structure is undergoing transformation, including the creation of a strategic command in the United States responsible for the continuing transformation of Alliance military capabilities.

The Prague package also included a Civil-Emergency-Planning Action Plan to assist national authorities in improving their civil preparedness; improved intelligence sharing and assessment arrangements; improved crisis-response arrangements, including a new air defence concept for dealing with "renegade" aircraft, so that procedures are in place to deal with a repetition of 9/11; streamlined arrangements for deploying AWACS aircraft where needed; and increased cooperation with Partners, with a Partnership Action Plan against Terrorism [see article Working with Partners to fight terrorism by Osman Yavuzalp in this issue of NATO Review].

In addition, Alliance leaders endorsed implementation of five nuclear, biological and chemical weapons defence initiatives, which will enhance the Alliance's capabilities against weapons of mass destruction. These are a Prototype Deployable NBC Analytical Laboratory; a Prototype NBC Event Response team; a virtual Centre of Excellence for NBC Weapons Defence; a NATO Biological and Chemical Defence Stockpile; and a Disease Surveillance System. NATO is also strengthening its capabilities to defend against cyber attack and has initiated a missile defence feasibility study to examine options for protecting Alliance territory, forces and population against the full range of missile threats.

NATO's new military concept for defence against terrorism sets out four categories of possible military activity by NATO. These are anti-terrorism; consequence management; counter-terrorism; and military cooperation. In this context, anti-terrorism means defensive measures to reduce vulnerability, including limited response and containment actions by military forces and such activities as assuring threat warnings, maintaining the effectiveness of the integrated air defence system and providing missile defence. Consequence management means post-attack recuperation and involves such elements as contributing planning and force generation, providing capabilities for immediate assistance, providing coordination centres, and establishing training capabilities. Counter-terrorism means the use of offensive measures, including counter-force activities, both with NATO in the lead and with NATO in support of other organisations or coalitions involving Allies. And military cooperation covers among other things cooperation with Russia, Ukraine, Partners, Mediterranean Dialogue countries and other countries, as well as with other organisations, including the European Union, the Organisation for Security and Cooperation in Europe, and the United Nations.

Even NATO's science programme, which has traditionally focused on encouraging cooperation between scientists from different countries, has been redesigned in such a way that it, too, is now addressing efforts relevant to defence against terrorism, especially within the context of the Euro-Atlantic Partnership Council and the NATO-Russia Council.

Implementation of what is an impressive package of measures and initiatives may still prove problematic. Even if countries do live up to their commitments, NATO itself will have to change the way in which it operates to reflect the requirements imposed by a new strategic environment. Although the Alliance will soon have 26 members, the organisation's working methods have remained largely unchanged from those developed for an Alliance of twelve.

Here again, the Prague Summit has made a good start since NATO leaders agreed to reduce the numbers of committees — currently more than 450 — by 30 per cent. More decisions will in future be pushed towards subordinate committees, leaving the North Atlantic Council more room to discuss strategic issues. The procedures for ministerial meetings have been streamlined as well, sacrificing formality in order to gain time for more substantive exchanges. Over time, these changes should lead to a different working culture within the Alliance.

NATO has moved a long way since 9/11 to be able to contribute effectively to the war on terror. Nevertheless, many issues related to this war remain controversial and achieving consensus on concrete actions may prove difficult. Indeed, in many ways, the situation today concerning NATO's role in the war of terror is akin to that in 1994 or the first half of 1995 concerning taking on out-of-area missions in the former Yugoslavia. That said, the rift within the Alliance was probably greater in the 1990s over policy towards Bosnia and Herzegovina than it is today, though its nature is clearly different today because this time the United States has a vested national interest at stake.

NATO came to terms with the problem in the 1990s. Whereas it took three-and-a-half years of war for NATO to intervene in Bosnia and Herzegovina, the Alliance took action to stop the fighting in Kosovo after one year and NATO deployed preventively in the former Yugoslav Republic of Macedonia* to forestall greater conflict. In this way, the Alliance demonstrated that, although it might take some time to adapt to a new security paradigm, once it does adapt, NATO learns its lessons fast and delivers results when tested.

It took the Srebrenica massacre to persuade Allies of the merits of the initial intervention. The challenge today, therefore, is to achieve consensus around the best strategy to address the threat posed by terrorism and the proliferation of weapons of mass destruction without another such atrocity.