It would be interesting, indeed, to figure out if there is simply enough on this planet. If we flattened the income curve, would we eliminate want? This would answer a critical question about the sustainability of our current system, as well as question the morality of our system.
My believe is that, in this circumstance, want would be eliminated. When you hear statements like "the cost of one long-range bomber would feed all the world’s hungry", it gives great credence to this vision. What such a mechanism would look like has yet to be fully visualized, at least in a way that doesn’t mandate violent redistribution. Unless one considers the ideologies of Christ, Buddha, and the like.