I think it'll play into Fallout 4 because the story will be another struggle. 'War does not determine who is right, only who is left.' It was a joke made by Wadsworth in Fallout 3, but I don't think any phrase has rung truer regarding the Fallout universe than that one. That struggle will then be succeeded by another struggle, and that by another, and so on, with all of them going on in a background of meaninglessness. What 'war, war never changes' means to me is that there will always be some sort of struggle, and that struggle will always have a conclusion. Caesar's Legion would probably collapse without Caesar there to lead it. A great example is the degradation of the NCR into the same state of corruption as the U.S. No matter what great things 'chosen ones' do, they end up becoming corrupted/perverted by human nature and ultimately undermine themselves. Some form of contextualized morality seems to exist, but other than that, the world itself seems utterly devoid of meaning. To me, Fallout seems to be borderline nihilistic in the sense that history-and, indeed, life in general-has no purposeful progression or meaning.