> In the hopefully not too distant future, when humanity grows out of its barbaric infancy and we cease to kill each other over petty disputes a long term global renewal project will commence.

What could cause this change?

What could be different tomorrow compared to the past many thousands of years of wars that will stop wars from happening?

War is pretty simple in the general sense. Limited resources (land being the main one), and selfish people. We have more technology today, yes, but we let the population explode so land resources are still quite limited.

If you're expecting people to just 'wake up' I'm afraid that wont happen now for the same reasons it did not happen in the past.

Cultures ebb and flow. You cannot expect anti-selfishness culture to be a forever-lasting deterrent to war.