Recently I was in a class at school where I was learning about the Abyssinia Crisis, which took place in the 1930s. The Italians invaded Abyssinia with advanced weaponry, including poison gas, for the sole reason of wanting more land. TheAbyssinians only had spears as defense. I couldn't help but be reminded of the Destruction of the Hometree scene in Avatar, in which the RDA destroyed the Omaticaya's home for the reason of wanting that land and they had the more advanced technolgy, which included gas; all the Na'vi had were bows and arrows as defense. I don't think that there's a coinsidence. I think Cameron was using the events of the war as influence.