I am not sure whether 'world peace' would actually be a good thing... Sounds wonderful and no-one really likes war and conflict after all, with all the pain and suffering it causes. But would we not all die of boredom instead? Not to have that wonderful and impressive military hardware to look and wonder at.... mmmmmm
And then, of course, has not conflict driven human developement in many positive ways. Is not conflict a necessary part of what makes us human and drives us forward.