It would have been in the 70s -- which is why USD support has remained despite the Nixon shock for a few more decades. By now, most central banks and governments are increasingly, dare I say "prepared" or slowly preparing for the possibility without it impacting their economies or trade too badly. Nobody wants to see the USD fail or die --- but day-to-day economic / monetary policies on US soil should become less and less of a rest-of-the-world economic worry, concern or impact compared to previously.

Now, the last remaining problem is savings of millions tied up in USD promises worldwide. Still a big problem, and rest assured the USD will continue to get "support" to the proportion that these savings haven't "migrated" over to "something else" yet.

Anyway, one day all these notes the US has been "exporting" globally for many years will come home one way or the other. Hope the new cash supplies won't, ahem, "overwhelm" a struggling domestic economy at that time, shall we?