The Russian military plane that entered Sweden’s airspace briefly on Friday was interpreted as an unsubtle warning to the country as it debated joining Nato alongside its neighbour Finland.
Russia has repeatedly warned of “serious military and political consequences that would require an adequate response” should the two Nordic nations apply for Nato membership, an increasingly likely prospect.
Joining Nato would mean Sweden and Finland were covered by the Article 5 collective defence commitment that ensures an attack on one member generates a response from the entire alliance. But what particularly worries both countries is the period before they became official members, when no such guarantee would apply.