tance since its implementation in the context of the Paris terrorist attacks in November 2015.
Despite the importance of the ongoing processes, the EU will, for an indefinite period of time, remain far from NATO in terms of its hard security capacities. The strengthened military tension in Europe stresses this relationship further. The Union’s command structure is tiny in comparison with NATO and its key foci in terms of planning and capabilities lie in tasks other than collective defence. With a significant number of EU members also being members of NATO, the Union’s role has been to attempt to advance European security through its comprehensive political and economic tools, rather than by operating primarily with military instruments.
In this respect, the EU’s mutual defence clause (TEU, Art. 42.7) has a different character, as it deals with hard security and obligates all EU members to defend an EU country in the event of armed aggression. The firm obligation is softened by its character as an obligation between the member states. As defence of a member state in such a situation is not conferred to the EU (as distinct from the solidarity clause, TEU, Art. 222) but to the partner states, the clause does not give rise to joint systems of planning and command. Any arrangements on aid and assistance will in these conditions remain on a bilateral basis between the targeted country and the others. The activation of the clause at the request of France after the terrorist attacks in November 2015, however, is likely to make it a living part of the EU and to lower the threshold for its use.
All in all, irrespective of their largely overlapping memberships and military resources, NATO and the EU will remain separate actors in the field of European hard security. Existing structures and cooperation allow the EU, and its member states, to respond to a wide range of low-intensity conflicts without NATO. When it comes to major military conflicts of a traditional or non-traditional character, it is still NATO with its military and political assets that would be the prime mover, and whose credibility would immediately be at stake in an Article 5 contingency.
On the other hand, it is equally unthinkable that the EU mutual defence clause would not become activated in a major European conflict. The main result of its activation together with NATO’s defence clause would concern the involvement of the EU’s six non-NATO countries (in particular Finland and Sweden) in the conflict. Their participation would require
