But between 1900 and 2000 , roughly 10 billion lives were lived -- meaning that just 1-2 % of the world 's population died violently . Since 2000 , U.N. says the risk of violent conflict has fallen to 10 % . In perhaps greatest paradox in history , what 's made the world safer is war itself , Ian Morris says . War seems to be only what people have found to create peaceful societies , he argues . Morris : World has single great power -- USA -- capable of deterring governments from using force .
Since 2000 , U.N. says the risk of violent conflict has fallen to 10 % . In perhaps greatest paradox in history , what 's made the world safer is war itself , Ian Morris says . War seems to be only what people have found to create peaceful societies , he argues . Morris : World has single great power -- USA -- capable of deterring governments from using force .