Latest News

NATO Articles 4 & 5: What are the alliance's obligations as drones begin to appear in Europe

Denmark announced on Thursday that it is weighing up whether or not to invoke Article 4 in the founding NATO treaty, after overnight drone incursions temporarily shut down two of its airports as well as military installations located in western Jutland.

Danish Defence Minister Troels Poulsen called the incursions "hybrid" attacks designed to instill fear, but admitted he didn't know who was behind it.

Mette Frederiksen, the Danish Prime Minister, had earlier linked drone incursions similar to those that temporarily closed Copenhagen Airport overnight and into Tuesday morning with a suspected Russian drone invasions as well as other disruptions in Europe. Moscow denied any involvement.

What happened?

Danish police reported that drone incursions caused the closure of Billund Airport, Denmark's second largest airport, for one hour. Aalborg Airport, which is used for both commercial and military flights was also closed for three-and-a half hours. Both airports reopened Thursday.

Police reported that drones were seen over night near the airports of Esbjerg, Sonderborg and Skrydstrup, which is home to F-16 and F-35 fighters from Denmark, and a military installation in Holstebro.

All the affected areas are located on the Jutland Peninsula in western Denmark.

Danish authorities have decided to not take down any drones that are in their airspace, for safety reasons. This is despite the disruption to air traffic.

What is Article 4?

According to Article 4, members of the North Atlantic Treaty Organization must consult each other whenever they believe that the territorial integrity, political independence, or security of a member is in danger.

Article 4 of the North Atlantic Council's charter, which is NATO's principal decision-making body, could lead to a joint decision or action.

Defense Minister Poulsen stated that the Danish government is currently holding internal and NATO discussions on whether or not to invoke Article 4.

It would be the second such incident this month. On September 10, the Polish Prime Minister Donald Tusk invoked Article 4 after Poland shot down drones that were flying over its airspace, following what he described as a "large scale provocation" from Russia.

The Russian defence ministry has confirmed that its drones have carried out an airstrike on military installations in western Ukraine, but it did not intend to strike any targets in Poland.

Many European officials described this incursion as an intentional act and an indication of Russian escalation.

In February 2022, Bulgaria, the Czech Republic and Estonia, Latvia, Lithuania as well as Poland, Romania, Slovakia, and Slovakia invoked Article 4 in response to Russia's invasion.

What is Article 5?

If it were proven that Russia had attacked the territory of an NATO member state, then the focus would shift to Article 5 of the founding treaty of NATO.

The alliance was formed in 1949, with the U.S. as its mainstay. Its purpose was to fight the Soviet Union and the satellites of the eastern bloc during the Cold War.

According to the charter, "the Parties agree" that any attack on one or more in Europe or North America will be considered as an attack on them all.

It says: "They agree that if an armed attack takes place, they will, in exercising their right of individual or group self-defense, recognized in Article 51 of the Charter of the United Nations by each of them, assist the Party(ies) so attacked, by taking immediately, individually and with the other Parties in concert, whatever action is necessary to restore and maintain the safety of the North Atlantic region, including the use of force."

How could the Ukraine War trigger Article 5?

As Ukraine is not a member of NATO, the full-scale Russian invasion that took place in February 2022 didn't trigger Article 5. However, the United States and its other members rushed to offer military and diplomatic support to Kyiv.

Experts have warned for years about the possibility of a spillover into neighbouring countries along NATO's east flank, which could force the alliance militarily to respond.

This action, whether intentional or not, by Russia has increased the risk that the war will spread by bringing other countries into it.

Is it automatic to invoke Article 5?

No. After an attack on one member state, other members meet to decide if they are willing to treat it as an Article 5 case.

Experts say that the language used is flexible enough for each member to decide what to do in response to an armed attack against another.

Article 5 was activated by the United States in response to September 11, 2001 hijacked plane attacks on New York City and Washington. (Reporting and editing by Timothy Heritage Gareth Jones Peter Graff, Matt Spetalnick, Charlie Devereux)

(source: Reuters)