Correction: to not have to fight Russia. The EU falling apart is Putin's wet dream because he's very afraid of a confrontation with the whole bloc, and wants to subjugate the small European countries piecemeal (and yes, on their own, they would have to submit or face missiles/drones or, even worse, human meatwave attacks by a foe that has been whipping its populace into a death cult for decades for exactly that eventuality).