As long as human beings have existed – there have been conflicts. And today, war, or the preparation for war, is something many modern societies need to cope with but also depend upon. A flip side to the atrocities of war is that the military industry plays a big role in creating jobs, tax income and economic growth. And military research and development haves, besides creating horrible weapons, also sparked countless technical innovations we now take for granted. Some even argue that without wars our economies would tank completely. But are wars really a necessity of the human existence? Could we manage to create a truly peaceful world? And would we be able to afford it?