Is the USA so powerful because of any intrinsic good qualities? Probably not. A quick look at global military expenditure shows exactly why the USA has so much clout globally. 640.0 $Bn. speny by USA. Russia only spent 87.8 $Bn. in the same year.
http://en.wikipedia.org/wiki/List_of_countries_by_military_expenditures
http://en.wikipedia.org/wiki/List_of_countries_by_military_expenditures