International transactions were growing in importance, and countries were less willing to have their domestic macro-economic objectives subordinated to considerations of fixed exchange rates and balance-of-payments equilibrium.
This issue came to a head in the late 1960s, when the United States was not prepared to adopt restrictive domestic policies to stem a dollar outflow when it was trying to finance domestic social reforms and the Vietnam war at the same time; and its partner countries were unwilling to accept the domestic inflationary consequences of a continued peg to the US dollar.