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Collective Defence

When NATO was founded in 1949, it wasn't just simple handshakes that sealed the deal between the 12 founding nations. The Alliance established itself by creating a unanimously agreed upon set of rules and duties and by setting the basis of the North Atlantic Treaty with 14 articles.

NATO, and much of the world, were picking up the pieces in the aftermath of World War II when the North Atlantic Treaty was signed in Washington D.C. in 1949. The initial aim of the treaty was to create a pact of shared support and collective defence as NATO faced the risk that the Soviet Union would extend its control over Eastern Europe and other countries.

The heart of the Treaty and key to collective defence is Article 5, which declares that if any single Ally is the victim of an armed attack, every other member of the Alliance will consider it as an attack against all members.

If Article 5 is invoked it's the Allies' obligation and responsibility to identify the necessary actions to undertake in that situation under the given circumstances. Each member can provide any form of assistance they think is necessary to support the attacked Ally and "to restore and maintain the security of the North Atlantic area." The support can, but isn't mandated to, be military and it also depends on the resources (material and personnel) of each member country. As written in Article 5 the consultations for these decisions are not just individual, they also should happen in concert with all other parties to find the best solution.

The first time in NATO's history Article 5 came into use was after the terrorist attacks on 11 September 2001 in the United States. NATO members invoked Article 5 less than one day after the attacks. Invoking Article 5 led to Allies showing solidarity with the United States, but it also started a sequence of actions for NATO: from investigations into if the attacks are covered by Article 5, consultations among Allies and to a package of collective measures established by NATO.

Member nations agreed on enhanced sharing intelligence information relating to the threats posed by terrorism in an effort to assist other Allies or other countries that could become targets of terrorist attacks. Other measures included providing enhanced security for facilities within the United States and other Allied territory and providing access to United States' and other Allies' ports and airfields for counterterrorism operations.

The Alliance also launched several operations after the 9/11 attacks. "Eagle Assist" was an operation where 7 AWACS (Airborne Warning and Control System Aircraft) patrolled the skies over the United States. "Active Endeavor" incorporated elements of NATO's Standing Naval Forces, which monitored the Eastern Mediterranean to detect and deter terrorism and illegal trafficking.

Terrorism was already recognized as a threat to NATO's security, but the reaction to 9/11 was the first time that the Alliance began to actively fight against terrorism and launch operations outside the Euro-Atlantic area.

However, collective defence measures are not only triggered by events like 9/11. NATO perpetually supports the Allied and partner collective defence. The Alliance has Standing Maritime Forces, which are ready to take action when called upon. Additionally, NATO conduct's multiple peacetime air policing missions to help track and identify violations of airspace.

This concludes part eight of the SHAPE Public Affairs' series "Knowing NATO". As this is the last entry in the series, our team would like to thank you for watching, reading, and learning with us about our great Alliance.

Video by SHAPE Public Affairs Office

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