The Atlantic Alliance and the principle of Collective Defence

The principle of Collective Defence, enshrined in article 5 of the founding treaty of the North Atlantic Treaty Organisation (NATO), represents the cornerstone of NATO's founding and the bond of unity between NATO member states.

This principle states that an armed attack against one or more NATO member states, whether in Europe or North America, "shall be considered as an attack directed against all of them". Collective Defence thus becomes a right and a duty that Alliance countries are committed to guaranteeing.

So far, article 5 has been invoked only once, in 2001, following the 9/11 terrorist attacks on the Twin Towers in New York and the Pentagon in Washington.

On 2 October 2001, the Secretary General of the North Atlantic Treaty Organisation (NATO), Lord Robertson, addressed the international community to announce, for the first time in history, the invocation of Article V of the Washington Treaty:

The principle of Collective Defence, enshrined in Article V of NATO's founding treaty, represents the cornerstone of NATO's founding and the bond of unity between NATO member states.

The Treaty of Washington was signed in 1949 by ten countries (Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, the Netherlands, Norway, Portugal, the United Kingdom, the United States and the United States) from both sides of the Atlantic Ocean, giving birth to the North Atlantic Treaty Organisation, an alliance based on a commitment to defend each other in the event of armed aggression against any of its member states.

Thus, the first alliance between North American and Western European countries was born, based on the inherent right of individual or collective self-defence in the event of armed attack, as enshrined in Article 51 of the United Nations Charter².

Today, NATO is made up of 30 states, including Spain's accession in 1982, willing to support the principles of the founding treaty and ensure the security of the Alliance.

NATO operates on the premise of "one for all, all for one". This principle is reflected in Article V of the Washington Treaty, the principle of "Collective Defence":

"The Parties agree that an armed attack upon one or more of them, occurring in Europe or North America, shall be considered as an attack directed against them all, and accordingly agree that if such an attack occurs, each of them, in the exercise of the right of individual or collective self-defence, recognised by Article 51 of the Charter of the United Nations, shall assist the Party or Parties so attacked, and shall thereupon take, individually and in agreement with the other Parties, such measures as it deems necessary, including the use of armed force, to restore and maintain security in the North Atlantic region.³"

Article V of the Treaty is complemented by Article VI which stipulates in which situations an attack shall be considered an "armed attack against one or more of the Parties". The article refers to attacks directed against the territory of any Member State of the Alliance, or under its jurisdiction; and against its Armed Forces: 

"Against the territory of any Party in Europe or North America, against the French departments of Algeria, against the territory of Turkey or against the islands under the jurisdiction of any Party in the North Atlantic area north of the Tropic of Cancer.

Against the forces, ships or aircraft of either Party in these territories, as well as in any other region of Europe in which occupation forces of either Party were stationed at the date of entry into force of the Treaty, or which are in the Mediterranean Sea or in the North Atlantic region north of the Tropic of Cancer"⁴.

NATO Member States undertake to ensure the collective defence of the Alliance through necessary assistance and support. Each Allied's intervention is considered an individual obligation and responsibility. It is also determined by each State in the light of the current situation and particular circumstances.

The response need not necessarily be military. It will be carried out in a coordinated manner and in accordance with available resources. However, each state will be responsible for deciding its contribution, taking into account the purpose of Article V "to restore and maintain the security of the North Atlantic area"⁵.

To date, Article V has been invoked on only one occasion, in September 2001.

Following the attacks of 11 September 2001 on the World Trade Center in New York, USA, perpetrated by the jihadist terrorist organisation Al-Qaeda, the international sphere was confronted with an event that would mark a turning point in international security policy. 

An attack of such magnitude required an effective and efficient response. Thus, after reviewing the events, NATO invoked for the first time in its history the application of Article V of its founding treaty, Collective Defence.

With these words, 24 hours after the attacks were committed, it declared al Qaida's responsibility and categorised the attack as an armed attack against the Atlantic Alliance:

Since its global emergence, the phenomenon of terrorism had been categorised by NATO as a threat to its security. However, the commission of the 9/11 attacks and the spread of terrorist activity prompted the Alliance's commitment to counter-terrorism and the launch of a reactive campaign, promoting the first military operations outside the Euro-Atlantic area and adapting its capabilities to emerging needs.

NATO's response to the attacks and its support for the United States resulted in the launch of two operations and the adoption of a package of eight measures aimed at combating the terrorist threat.

The first counter-terrorism operation, known as Eagle Assist, was launched in October 2001 and concluded in May 2002⁷. Seven NATO AWACS surveillance aircraft were deployed to patrol the US skies. In total, 360 flights were conducted.

On 26 October 2002, the second counter-terrorism operation was launched in response to the 9/11 attacks. The operation, known as Active Endeavour , involved the deployment of NATO Standing Naval Forces to patrol the Eastern Mediterranean, monitor maritime activity and deter potential terrorist activity in the area. In March 2004, the scope was expanded throughout the Mediterranean Sea.

In July 2015, the North Atlantic Council approved the replacement of Active Endeavour⁸ with Operation Sea Guard, a "Non-Article 5"⁹ mission that continues today with the participation of Spain as a Member State of the Alliance. 

The eight measures implemented by the Atlantic Alliance in response to the al-Qaida attacks in the United States and to address the international terrorist threat were as follows:

1. M1. Improve information sharing and cooperation, both bilaterally and within the appropriate NATO bodies, regarding the terrorist threat and the measures to be taken to combat it.
   2.    Provide assistance, individually or collectively, to Allies and other countries that may be subject to terrorist threats as a result of their support for NATO's counter-terrorism efforts. 
   3.    Take necessary measures to ensure the security of United States and other Allied facilities on their territory.
   4.    Strengthen Allied countries' resources and assets necessary to support counter-terrorism operations.
   5.    Authorise military overflights of US and other allied countries' aircraft in the context of counter-terrorism operations, in accordance with air traffic agreements and national regulations. 
   6.    Provide access for the United States and other allied countries to national ports and airfields of NATO Member States in support of counter-terrorism. 
   7.    Commitment to deploy NATO Standing Naval Forces throughout the Eastern Mediterranean to deter and demonstrate their capabilities.
   8.    Commitment to deploy NATO Airborne Early Warning Forces in support of counter-terrorism¹⁰.

Since the first invocation of Collective Defence, the Member States of the Atlantic Alliance have had to deal jointly with the terrorist threat in its various forms and other threats to international security, from global warming to the rise of cyber-attacks to the global pandemic of COVID-19.

Over time, the international playing field has been characterised by a changing and complex scenario with the intervention of a variety of state and non-state actors and the emergence of new hybrid threats.

NATO's commitment to its member states has translated into responsiveness to their demands and needs. With respect to the invocation of Article V, the Alliance continues to develop activities and operations as part of its efforts to secure the peace of the Atlantic area.

At the request of Turkey, a member since 1952, NATO has on several occasions implemented measures under the principle of Collective Defence. The most recent were in 2003, with the approval of a package of defensive and deterrent measures during the Iraq crisis, known as Operation Display Deterrence¹¹. In 2012, with the deployment of Patriot missile systems in response to the crisis situation in Syria.

Spain is currently participating in NATO's Active Fence defensive mission whose main objective is to protect Turkey from possible ballistic missile attacks from Syria¹².  

In 2014, Russia's illegal annexation of Crimea and the increase in the global terrorist threat posed by jihadist organisations such as the Islamic State (Daesh) led to the largest increase in NATO Collective Defence operations since the Cold War.

Measures included a tripling of the NATO Response Force; the deployment of more than 5,000 troops as the Alliance's spearhead; the deployment of international military brigades in Estonia, Latvia, Lithuania and Romania; and intensified air surveillance over the Baltic States and the Black Sea.

In 2016, member states came together at the Warsaw Summit recognising, for the first time in history, cyber defence as a new common operational space for securing cyberspace and conducting cyber operations through the provision of allied services and capabilities.

Today, NATO provides Collective Defence, not only in response to ad hoc requests or events, but also through Standing Forces on active duty that contribute to Alliance efforts. 

NATO's Standing Forces make a continuous contribution to ensuring the security of the Atlantic area. These include the standing naval and air forces, integrated defence systems and the ballistic missile defence system.

NATO's standing naval force performs a range of tasks, from manoeuvres to operational missions, both in times of crisis and in peacetime. The air force carries out surveillance missions that enable NATO to detect and take appropriate action on any violations or infringements of NATO airspace. In addition, the integrated air defence system provides protection against air attack and includes NATO's ballistic missile defence system.

The concept of Collective Defence was coined in 1949 in response to the risks and challenges of the post-World War II era with the aim of ensuring security in the event of armed attack against Atlantic Alliance member states and their allies.

Collective Defence has made it possible to meet the transnational threats and challenges that have emerged since the second half of the 20th century, evolving along with societies.

However, the consolidation of new information and communication technologies, industrial advances and the impact of hybrid international threats have highlighted the importance of recategorising the concept of Collective Defence and adapting it to a new concept of security. In the 21st century, the emergence of new common spaces such as cyberspace, the presence of new actors on the international game board and the creation of new weapons of chemical and biological destruction pose a more complex scenario and the need to redefine the parameters of an "armed attack".

Not to mention that many threats considered traditional or "of the past" will return in the future, mutating and converging with contemporary ones. Who would have imagined that in 2020 society would experience a global pandemic that would lead to one of the most critical health crises in history. Or that pirates would steal and hijack ships, putting Europe's resource supply chain at risk.

Pino Penilla Marquínez/Cyberintelligence analyst and coordinator of the National Defence area of Sec2crime/ Secretary General of the Spanish Atlantic Youth Council (COAJE- YATA SPAIN).

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