The US economy saw high inflation in the '60s-'70s due to a mix of monetary and fiscal policies. In the '80s, inflation dropped when fiscal policy and agents' beliefs changed. If the monetary authority had always led or if agents had been confident about this switch, the Great Inflation wouldn't have happened. The policy change in the '80s led to lower inflation, reversed debt-to-GDP, and decreased inflation persistence and volatility. Without this change, inflation would have stayed high for fifteen years.