Lets say the United States attacks Canada. Would it be right for Canada to let this happen? By defending itself, a war would erupt between both countries, but Canada would be achieving an act of self defense. Examples like these have been usually the main cause of wars, and only until recently have the subjects and reasons begun to change. Yes, it is unethical to attack an other country for territory and power, but that is not considered war. In the example, once "Canada" reacts, then war would be officially declared. This scenario would be ethical because Canada would be defending itself by using war as its excuse. One of the only ways for humans to force their opinions on other groups is to use war. Using actions like peace talk and political disputes cannot force other countries to submit to any rule. Deals are usually cheated, and because war has few rules, it is the only way for groups to force an action on others. After a country loses a war, it is almost impossible for them to deny any influence from the winner. This is why war is right because it is usually an expression of defense and human argument and decision. It helps develop society and it makes the final decision on what changes should be made in the world. War is for the greater good, because when changes in society are necessary, sometimes humans need to fight for what is right.