As I understand it, most economists (certainly, most economists whose opinions matter to central bankers) believe that a small rate of inflation, perhaps 1-2% a

As I understand it, most economists (certainly, most economists whose opinions matter to central bankers) believe that a small rate of inflation, perhaps 1-2% annually, is a Good Thing, since it encourages savers to invest in productive companies rather than just stuffing greenbacks under their mattresses. So "I guarantee you the dollar will buy less 10-20 years from now" is a pretty safe bet, regardless of the general political and economic situation.