The art of war exists in nature

Around 2% of Irish mute swans die in fights. As spring approaches, mature males, known as ‘cobs’, stake out ‘territories’ on ponds, lakes and rivers. Each one keeps rivals at bay so that his ‘pen’, and their cygnets, will have the resources to see them through to autumn.

When challenged, a cob may fight. Violence, however, can result in injury or death, so it’s avoided if at all possible.

Manoeuvres, propaganda and the calculations of military intelligence, help quarrelling nations avoid disastrous wars. It’s the same for swans.