“We need jaw jaw not war war”, said Winston Churchill rather hypocritically. Still, he would be glad to see that the number of wars around the world has fallen dramatically since the end of World War 2, despite the wars in Korea, Africa, Afghanistan, Iraq, Libya, Lebanon, Pakistan versus India, Central America, Cyprus, ex-Yugoslavia, Syria and now Yemen. Compared with centuries past this has been a remarkable era, yet one not often acknowledged. Interstate wars, apart from India versus Pakistan, Afghanistan, Saudi Arabia and Yemen, have vanished off the map. The wars that remain are civil wars. The democracies do not go to war with each other, as British Prime Minister Margaret Thatcher long ago observed. According to a detailed study made by the Economist last month, analyzed all international wars since 1900, along with the belligerents’ wealth and degree of development. It counted all conflicts in which at...