For ar least 5 years I don't thinks it's a threat! The world is only getting used to the cryptocurrency, even though many ordinary people in doubts! In 5 years time, from today, during this period I thinks USA will definitely, if not yet allready came up with their own crypto that will replace or get tied up to the dollar! USA politicians will never let the dollar die or let the dollar to be replaced in trade, as they have strong economy and a whole world trades their products, they will make something up, I repeat if already havn't done so!