Fair point, but the fact that trading oil exclusively in dollars is of major importance for the US economy still stands. Are nuclear weapons or selling oil in other currencies the cause of an invasion? It's up for debate and so we can't be certain which one's the propaganda; they could be both or neither for all we know (Obviously if you're from the US you're more likely to hear the nuclear arguement and if you're from the Middle East the same goes for the oil arguement).