World Peace

All the good little boys and good little girls wish for peace in the world. No conflict, no hatred, a world in which guns are thrown away and everybody has good relations. No war. But, what would it take for such a thing to take place? A change in the population in which everybody has no opinion, where everyone is the same? A surplus of resources and good conditions everywhere? An outside threat to everyone that creates unity? What does it take to create world peace?
A change in which everyone becomes the same doesn't seem like the optimal choice in this utopia, and it certainly doesn't seem very realistic. Differing views stem from differing conditions in the environment and possibly genetic make-up, which creates variation among individuals. A surplus of resources and good conditions might work, but it would require a miracle for something like that to happen, and plus this surplus will contribute to the growing global population, and soon there wouldn't be enough to feed everyone again, so conflict over resources would yet continue. An outside threat to everyone could possibly work, foreign terror can be a powerful unifying force, as individuals usually band together in the face of adversity(ex. the September 11th, 2001 terrorist bombings on the Twin Towers), but it could also work in the opposite direction, panic and confusion could drive different groups of people against each other, creating a divisive force in the population.
These are some theoretical situations in which all peoples of the world form friendly bonds with one another and end all wars (or conflicts) in the world. But what would actually work? Can you think of some things?
~C.