dollars
the world uses dollars as it currency. at least they have been for quite some time. that gives americans a huge economic advantage. one wonders why dollars occupy such an exalted position. well, a goodly part is because america is a good investment. ie we repay our debts. or at least we have in the past. our debt ratio is high enough that foreign investors ought to be feeling a bit wobbly. like maybe they should shop around a little.