Neither loose monetary policy, nor big-spending fiscal policy can grow an economy. All that these policies can do is to redistribute a given pool of real savings from wealth generators toward non-wealth generating activities.
In the blurry world of conflicting economic indicators and forecasts and policy surprises, activist policymakers at the Fed do not know exactly what the “right” monetary policy is today. Neither do their activist critics.
Loose monetary policy can appear to work so long as real wealth is expanding. But money expansion weakens wealth creation over time, eventually leading to slower growth, lost wealth, and economic busts.