Warfare: an Invention- Not a Biological Necessity

In her paper, War: An Invention- Not a Biological Necessity, Margaret Mead says that "…warfare, by which I mean organized conflict between two groups as groups, in which each group puts an army (even if the army is only fifteen Pygmies) in the field to fight and kill, if possible, some of the members of the army of the other group- that warfare of this sort is an invention like any other of the inventions in the terms of which we order our lives, such as writing, marriage, cooking our food instead of eating it raw, trial by jury, or burial of the dead, and so on." Mead backs up this statement by telling about the Eskimo people, who have no sense of warfare.
If warfare was just a natural instinct that all humans had then all groups of people around the world would use warfare to further their civilization. Instead, since warfare is an invention of man instead of a natural part of humanity some groups around the world no nothing of warfare whatsoever. Along with these groups there are also many groups, like the Pueblo Indians who only used warfare to defend their civilization, and did not use war to expand their own lands and influence. Had it not been for another group bringing war to them they would have most likely never partaken in war themselves.
As far as war becoming obsolete, that is unlikely to happen. Because while better ways to resolve our conflicts are known, they have been known for many centuries and warfare has still thrived. If every nation around the world were peace loving and strove to resolve its differences by means other than warfare then yes, war would become obsolete, but the human race has the tendency to hold onto its past. Governments do not want to change the way that they resolve conflicts much like people do not want to change the way they run their own everyday