(noun) preponderant influence or authority over others; domination / (noun) the social, cultural, ideological, or economic influence exerted by a dominant group
Thus in 1971 Europe was jettisoned from the dollar zone by a United States intent on preserving its hegemony and unwilling to turn to austerity to save Bretton Woods.
cus of the $35/oz of gold value being heavily tested in the late 60s/early 70s