The big float Jun 26,2021 - Last updated at Jun 26,2021 BERKELEY — August 15 is not a red-letter day on most calendars. True, August 15, 1969, was the first day of the Woodstock music festival. And the Panama Canal opened to traffic on August 15, 1914. Mostly, though, mid-August finds officials and others on holiday. But not on Sunday, August 15, 1971. That evening 50 years ago, at the conclusion of three days of crisis meetings, President Richard M. Nixon announced that the United States was preemptively closing the “gold window”, the financial facility through which the country made gold available to foreign governments and central banks at $35 an ounce. To contemporaries and historians alike, Nixon’s announcement marked the end, or at least the beginning of the end, of the Bretton Woods international monetary and financial system. And that meant it marked the end, or at least the beginning of the end, of American economic and monetary hegemony. The postwar period when the US could all but unilaterally determine the monetary structure and financial fate of the Free World was drawing to a close.