France has taken the European Union into uncharted territory by obliging the other 27 member states to come to its defence following the terrorist atrocities in Paris.
Invoking article 42.7, a never used clause of the EU treaty triggering mutual defence among the 28 member states, Paris admitted it was struggling to cope with its foreign military commitments while beefing up security at home in the wake of the attacks, and asked the rest of Europe to come to its assistance.
The request was supported unanimously in what Jean-Yves Le Drian, the French defence minister, described as an emotional and highly charged meeting of EU defence ministers in Brussels.
As a result of the train attacks in Spain in 2004, the EU inserted mutual defence measures into the Lisbon treaty similar to the Nato alliance’s article five, which obliges all member countries to come to the defence of one of their number if attacked.
As the EU does not have an army, the French will now conduct a set of bilateral negotiations with other EU states on what kind of military help might be available.
So what does this mean? Well it doesn't mean that the EU is at war, as the most sensationalist of media suggested yesterday.
But it does put the union in a position it has never been in before.
Some might call it a time of renewed solidarity in Europe after a year that's seen many cracks form on the edges of the union.
Or perhaps it may prove that only mutual fear can hold the EU together.