currency when the great expansion of globalization took place after the collapse of communism and the entry of china and india into the world economy. like the english language which has become the global business, the dollar is the convenient common denominator for global currency transactions. the alternatives are weak and euro is dogged about concerns about the future and swiss frank represents too small to represent a reserve currently and china hasn't earned enough to freely float its currency. the unusual role for the dollar gives the u.s. enormous power. but with power comes responsibility. and it is troubling to see washington wield it in such an arbitrary and high ended manner. as was pointed out, nothing lasts forever, the pound sist sterli sterling, the reserve currency for much of the 19th century, started to be overtaken by the dollar in the 1920s, history