600 people killed in 30 years in battle between the featured tribes. Population of New Guinea: 11.3 million.<p>Some of the battles are agreed upon ahead of time. Killing in battle is not usually considered murder <i>under law</i>, but even so, the <i>vast majority</i> of people do not murder.<p>The armed militia was also high on drugs when they confronted the motorists, so their very minds (nature) were changed during the encounter.