This article is a short study of the dollar as a world currency, in which the advantages and disadvantages of this situation are presented. On the one hand the American economy has the benefit of a privilege, and this one is, for it, a source of difficulties. In addition, as a world currency, the US dollar is the currency of the imperialist contemporary system, centered on the United States. To neutralize the imbalances induced by this situation, it is not realistic to imagine that a world monetary system could be built as an abstraction. More realistically, one must examine the weak links of the imperial system and analyze how it could fissure and evolve.