Well, what's wrong with a little utopianism, haha? I really wonder whether Americans actually want world domination, or it simply has not yet occurred to most of us that there might be another possibility—that reducing our consumption of resources, eliminating the "need" to dominate the rest of the world with its associated military costs (in lives, dollars, and goodwill) might be an improvement in quality of life for both the US and the rest of the world. On a personal level, do you actually take the "I'll get mine and half of yours too, and if you don't like it, tough luck" attitude you've described above? Or is that the attitude you believe most Americans have, based on our past actions? If you meant the latter, I can't really disagree with you—but wouldn't voluntary simplicity be preferable?
I am not sure how to understand your last paragraph. Does "As for economies aimed at human quality of life, forget it" mean that you think Americans will never be sufficiently motivated by ideas of fairness or equal access to the world's resources to voluntarily reduce our own consumption thereof? Or are you saying that an economic system which has the goal of improving everyone's quality of life rather than relying on ever-increasing levels of consumption is doomed to fail—people only work because they have to (debt, "keeping up with the Joneses") not because they want to or to benefit others?