Putin's hybrid war with NATO explained

Unidentified drone sightings and violations by Russian jets in the skies over European nations in recent weeks have rattled NATO allies. Europe’s answer is to build a “drone wall”

It's essentially a defense system along the bloc’s eastern flank to repel unmanned aircraft from Russia, using British-made drones. 

So would it work? And how close are we to a full on NATO military confrontation with Russia?

Europe Editor James Mates tells Julie Etchingham what you need to know.