Long term rates are "normally" higher than short term rates to compensate investors for the likely risk that inflation will undermine the value of their bonds.
At this point there is no indication inflation may be about to accelerate. Some may recall that in the early spring of 1984, this work led us to conclude that 1984 inflation might be a lot lower than most then thought at the time. This section also includes comments on the possibilities of deflation and what might be expected if it does occur. It probably would not be the disaster some seem to think.