Last Thursday (14th January) the following the deadly terrorist attacks in Paris two months ago, a resolution was passed in the European parliament to invoke the EU treaty’s mutual defense clause and to ask for EU member states’ help in its “war” against the so-called Islamic State (ISIS). Furthermore, the Parliament also requested the EU foreign affairs chief Federica Mogherini to draw up guidelines for similar future cases, so as to avoid any need for temporary measures and explicitly involve EU institutions.

In legal terms the Mutual Defence Clause is the following:

If a member state is the victim of armed aggression on its territory, the other member states shall have towards it an obligation of aid and assistance by all the means in their power, in accordance with Article 51 of the United Nations Charter. This shall not prejudice the specific character of the security and defence policy of certain member states.

Commitments and cooperation in this area shall be consistent with commitments under the North Atlantic Treaty Organisation, which, for those states which are members of it, remains the foundation of their collective defence and the forum for its implementation.

The first and foremost of the French requests was the pooling of European military resources in support of France’s operations in Iraq and Syria. Secondly, they wanted reinforcements in other regions so the thinly stretched French military could be developed elsewhere where they are badly needed.

MEPs in the European Parliament were unanimous in their support of these measures. Nevertheless, they had some reservations when it came to the concrete measures. Most of them agreed that some member states will have to use EU institutions as facilitators in this task, as not every member state is capable of supporting France bilaterally against the so called Islamic State.

This effort also had the effect of highlighting a fundamental weak spot in the EU defence policy. The lack of guidelines on how the mutual defence clause should work has been one of the obstacles in mustering the resources needed to tackle the terrorist problem. Last week, the MEPs in the European Parliament called on Ms Mogherini to propose practical arrangements to ensure an efficient collective response in similar circumstances.

This would mean a reworking of some aspects of the European common defence policy. This has been long due in coming and the France’s invocation of the Mutual Defence clause could serve as an incentive to strengthen European security and defence. This is also a unique opportunity to create a common defence union, as pointed out by the MEPs.

The Resolution which was adopted by 406 votes to 212 states that the activation of the mutual defence clause is "a unique opportunity to establish the grounds for a strong and sustainable European Defence Union .. ready to face the overwhelming internal and external security threats."

However, MEPs stress the need by EU member states to look for ways to build more efficient cooperation among border management, police and other law enforcement agencies and to improve intelligence on the movement of weapons, explosives and terrorist suspects. They have also suggested setting up an EU civil-military headquarters to prepare contingency plans, inter alia for collective defence.