Mankind can move beyond war. As in, it is possible for this to happen, in a utopian global society. However, I doubt that mankind will move beyond war. It is the staple of foreign policy (a large sector of government policy, and therefore public policy) in the world, whether it be in the form of the prevention of war, or the prosecution of war. And being a pivotal part of the world, due to this, means that it is unlikely to be abandoned as a means to an end.